THE  LIBRARY 

OF 

THE  UNIVERSITY 

OF  CALIFORNIA 

DAVIS 


STATE  OF  CALIFORNIA 

DEPARTMENT  OF  PUBLIC  WORKS 

DIVISION    OF    ENGINEERING    AND    IRRIGATION 

EDWARD  HYATT,  Stale  Engineer 

BULLETIN  No.  14  CZ 

AZ 

The  Control  of  Floods  by 


Reservoirs 


By 
PAUL  BAILEY 


AN  APPENDIX 

to  the 

SUMMARY  REPORT 
TO  THE  LEGISLATURE  OF  1927 

on  the 

WATER  RESOURCES  OF  CALIFORNIA 

* 

and  a 

Coordinated  Plan  for  Tlieir  Development 


l-IBRARY 

52411  (UNIVERS.  1 Y  OF  CALIFORNIA 

PA  VIS 


TABLE  OF  CONTENTS 


Page 

FOREWORD     5 

ENGINEERING   ADVISORY    COMMITTEE 7 

ORGANIZATION ^ 8 

LIST   OF   PLATES 10 

LIST   OF   TABLES 11 

Ohapter  I. 

OPPORTUNITY  FOR  CONTROLLING  FLOODS  BY  RESERVOIRS 13 

Past  consideration  given  to  control  of  floods  by  reservoirs 13 

Future  conditions  favorable  for  use  of  reservoirs  in  controlling  floods 14 

Physical    opportunity    to    combine    conservation    and    flood    control    in    same 

reservoir 14 

Chapter  II. 

SYSTEMS  OF  FLOOD  CONTROL 18 

Leveed  channel  system 18 

Reservoir    system 18 

Combined  reservoir  and  leveed  channel  system 19 

Degree  of  protection  in  flood  control  systems 20 

Frequency  of  flood  occurrence 21 

Chapter  III. 

THE  PRINCIPAL  CHARACTERISTICS  OF  FLOOD  OCCURRENCE 27 

Regularity  of  flood  occurrence 27 

Time  of  year  of  flood  occurrence 27 

Limiting  dates  to  the  flood  season 29 

Date   of  greatest   flood   expectancy 36 

Preparatory  precipitation  for  flood  occurrence 36 

Limiting  values  of  progressive  rainfall  index  between  which  floods  occur 41 

Most  favorable  value  of  progressive  rainfall  index  for  flood  occurrence 49 

Relation  of  flood  occurrence  to  season's  run-off 50 

Chapter  IV. 

RESERVOIR  SPACE  REQUIRED  TO  DETAIN  EXCESS  FLOOD  FLOWS 53 

Source  of  information 53 

Method   of   analysis 53 

Relations    established 58 

Values    determined    60 

Variation  in  values  with  time  of  year  and  progressive  rainfall  index 62 

Chapter  V. 

THE  RESERVOIR  OPERATING   DIAGRAM  FOR  CONTROLLING  FLOODS.—  73 

Principles  of  oi^erating  reservoirs  for  controlling  floods 73 

The    reservoir   operating    diagram 74 

Reservoir  operating  diagram  for  controlling  floods  on  Sacramento  River 77 

Reservoir  operating  diagram  for  controlling  floods  on  Mokelumne  River 81 

Reservoir  operating  diagram  for  controlling  floods  on  San  Joaquin  River 85 

Reservoir  operating  diagram  for  controlling  floods  on  San  Gabriel  River 87 

Performance   of   the    four    illustrative    reservoir   operating   diagrams    in   con- 
trolling floods,  not  coordinated  with  conservation 90 


(3  ) 


TABLE  OF  CONTENTS— Continued 


Chapter  "VI. 

Page 

EFFECT  ON  CONSERVATION  OF  CONTROLLING  FLOODS  BY  RESERVOIR 

OPERATING  DIAGRAM 98 

Effect  determined  by  direct  test 98 

Kennett  reservoir  on    Sacramento    River 99 

An  alternate  rule  for  controlling  floods  by  reservoirs 105 

Pardee  reservoir  on  Mokelumne  River 118 

Temperance  Flat  reservoir  on  San  Joaquin  River 128 

San  (Jabriel  reservoir  on   San  Gal)riel  Iviver 138 

Performance   of   the   four   illustrative   reservoir   oi)erating   diagrains   in   con- 
trolling floods  when  coordinated  with  cf)nscrvation 198 

Chaptkr  VII. 

CONCLUSIONS    207 

Relialiility  of  analyses 207 

Accuracy   of  analyses 210 

Effect  of  length  of  stream  flow  record  upon  accuracy  of  deductions 210 

Geograi)hical  limitations  of  system  of  anaylsis 211 

Future  possibilities  of  improving  proposals  for  control  of  floods  by  reservoirs  211 

Chapter  VIII. 

TABLES  OF  MONTHLY  SUMMARIES  OF  WATER  AND  POWER  YIELD  OF 

RESERVOIRS  ON  THE  FOUR  ILLUSTRATIVE  STREAMS 21.'; 


(  4  ) 


FOREWORD. 


This  bulletin  is  one  of  a  series  api)ended  to  the  "Summary  Report 
on  the  Water  Resources  of  California  and  a  Coordinated  Plan  for  their 
Development"  that  was  presented  to  the  Leg^islature  of  1927.  It  is 
part  of  the  investigation  of  the  water  resources  of  the  state  conunenced 
in  1921.  This  invest ig'ation  has  comprised  a  survey  of  water  supplies 
and  flood  flows  throuj^hout  the  state,  a  determination  of  their  cliaracter- 
istics,  an  estimate  of  tlie  present  and  future  nee:ls  for  water,  and  the 
formulation  of  a  comprehensive  and  coordinated  plan  for  future 
development  in  order  to  insure  adequate  water  supplies  for  all  purposes. 
The  1927  report  concludes  this  investigjation.  The  entire  series  of 
bulletins  pertaining  to  the  1927  report  are : 

Bui.  12 — "Summary  Report  on  the  Water  Resources  of  California 

and  a  Coordinated  Plan  for  their  Development."      (A 

rejiort  to  the  Legislature  of  1927.) 
Bui.  13 — "The  Development  of  the  Upper  Sacramento  River." 
Bui.  14— "THE  CONTROL  OF  FLOODS  BY  RESERVOIRS." 
Bui.  15— "The   (Viordiiuited  Plan  of  Water  Development  in   the 

Sacramento  Valley." 
I'.ul.lG— "The   Coordinated   Plan   of  Water  Development   in   the 

San  Joaquin  Valley." 
Bui.  17 — "The     Coordinated    Plan    of    Water    Development    in 

Southern  California. ' ' 

Other  bulletins  pertaining  to  these  investigations  published  prior  to 
the  1927  report  are  : 

Bui.    4 — "Water  Resources  of   California."      (A   report   to   the 
Legislature  of  1923  on  the  first  two  years  of  investiga- 
tion.) 
Bui.    5 — "PloAv  in  California  Sti-eams. " 
Bui.    6 — "Water  Requirements  of  California  Lands." 
Bui.    9 — "A   Supplemental   Report   on   the   Water   Resources   of 

California."     (A  report  to  the  Legislature  of  1925.) 
Bui.  11 — "Ground  Water  Resources  of  the  Southern  San  Joaquin 
Valley." 

The  first  appropriation  for  the  investigation  of  the  Avater  resources 
of  California  was  made  by  Chapter  889  of  the  1921  Statutes,  in  the 
amount  of  $200,000.  This  resulted  in  the  publication  of  Bulletins 
Nos.  4,  5,  and  6.  These  contain  a  complete  inventory  of  all  the  waters 
within  the  State's  boundaries,  an  estimate  of  the  future  needs  of  water 
for  all  purposes,  and  a  preliminary  comprehensive  ])lan  for  ultimate 
development  that  will  secure  the  greatest  public  service  from  tlie  State's 
limited  water  supply. 

No  provision  was  made  for  tlie  continuance  of  tlie  investigations  by 
the  1923  legislature  but  at  the  urgent  request  of  the  farmers  of  the 
southern  San  Joaquin  Valley,  the  Cliambei-s  of  Commerce  of  San  Fran- 
cisco and  Los  Angeles  advanced  $90,000  for  the  study  of  a  first  unit 

( 5  ) 


of  the  comprehensive  plan  that  would  relieve  the  stress  in  a  section  of 
the  State  most  in  need  of  an  imported  water  supply.  With  this  money, 
works  were  planned  tliat  would  transport  tlie  surjdus  waters  of  the 
Sacramento  drainage  basin  into  the  San  Joaquin  Valley  and  make  a 
new  supply  available  for  the  southern  half  of  the  valley.  An  account 
of  this  work  is  published  in  Bulletin  No.  9,  a  report  to  the  Legislature 
of  1925. 

Chapter  477  of  tlie  1925  Statutes  made  $150,000  available  to  the 
Division  for  completion  of  the  work.  This  money  was  spent  in  perfecting 
the  "Coordinated  Plan"  of  development  rerpiested  in  the  appropriation 
bill.  Heretofore,  in  looking  to  the  future,  the  problems  of  flood  con- 
trol and  of  conservation  have  been  given  se])arate  consideration.  Expen- 
sive construction  programs  are  known  to  be  necessary  in  both  fields  of 
endeavor  to  provide  habitable  conditions  for  the  increasing  population. 
The  investigation  of  the  possibility  of  coordinating  these  two  necessary 
programs  has  assumed  such  large  proportions  that  this  entire  volume 
has  been  given  over  to  the  presentation  of  this  phase  of  the  "Water 
Resources  Investigation." 


(6) 


ENGINEERING  ADVISORY  COMMITTEE. 


This  bulletin  was  prepared  in  consultation  with  a  committee  of 
engineers  who  advised  in  the  working  out  of  the  "Coordinated  Plan." 
They  are : 

Louis  C.  Hill  B.  A.   Etcheverry 

J.  B.  LippiNCOTT  F.  C.  Herrmann 

Wm.  Mulholland  Walter  L.  Huber 

A.  J.  Cleary  a.  Kempkey 
G.  A.  Elliott 

Cooperating  with  committee: 

P.  E.  Bonner, 

District  Engineer,  U.  S.  Forest  Service,  representing  the  Federal 
Power  Commission  in  California. 

A.    V.    GUILLOU, 

Assistant  Chief  Engineer,  State  Railroad  Commission. 

L.  S.  Ready, 
Formerly  Chief  Engineer  of  State  i^ailroad  Commission. 

C.  S.  Ridley, 

Major,   Corps  of  Engineers,  U.    S.   Army,   member   and   secretary   of 
California  Debris  C^ommission. 


(  7) 


ORGANIZATION. 

B.  B.  MEEK Director  of  Public  Works 

EDWARD  HYATT Siate  Engineer 

This  bulletin  and  the  "Summary  Rei)ort  on  the  Water  Resources 
of  California  and  a  Coordinated  Plan  for  their  Development"  were 
prepared  by 

Paul  Bailey* 
A.  D.  Edmonston,  Princi])al  Assistant 


T.  B.  Waddell 
William  S.  Post 
A.  N.  BuRcii 
Gerald  Jones 


C.  B.  Meveu 
J.  II.  Peaslee 
R.  L.  Wing 


Chief  Assistants 

Percy  Jones 
A.  M.  Wells 
Chester  Marliave 
J.  J.  Haley,  Jr. 

Senior  Office  Eiigincrrs 

AV.  A.  Perkins 

E.  W.  Case 

G.  Stttbblefield 


Jiniior 
T.  Neuman 

L.    C.   JOPSON 

E.  W.  Roberts 

IT.    B.    GiLROY 

L.  N.  Clinton 
C.  W.  Roberts 
Laura  Munson 
Thomas  Clausskn 

B.  A.  Reber 
A.  W.  Reber 
L.  E.  Anderson 
P.  T.  Alexander 

C.  P.  Marshall 
William  J.  O'Connell 
II.  M.  Sturges 
Harold  White 

F.  Ij.  Blair 

II.  S.  Marshall 


Office  Enghieers 

Oscar  Blumberg 
J.  R.  Jahn 
D.  S.  Hays 
A.  P.  Bosworth 
J.  R.  Meskimmons 
W.  A.  Dorcas 
H.  Gerharz 
J.  H.  Knapp 
M.  II.  Blote 
p.  ii.  lovering 
Thomas  Lewis 
W.  R.  McLean 
P.  W.  Porter 

II.    N.    SULLIGER 

V.  GiVAN 

J.   H.  McCoRMICK 

D.   S.   Cleavinger 
II.  L.  Butler 


Delineators 
Jos.  T.  Maguire 
E.  N.  Sawtelle 
C.  L.  Greene 
J.  W.  McPartland 


•  Pornu  rly  Director  of  Public  M'orks  and  Slate  Engineer  (lesiKncd  Aupriist  'ii. 
1027).  Mamisrript  c()nii)l<'tod  for  publication,  after  resignation,  through  courtesy  of 
B.   B.  Meelt,  Director  of  Public  Work.s. 

(  S  ) 


Field  Engmeers  and  Topographers 

H.  S.  Williams  F.  L.  Elam 

E.  D.  Stafford  J.  H.  Gibson 

J.  F.  Taylor  Millard  Dawson 

C.  C.  Vance  Ray  Vernon 
Glenn  Lang  Ward  Eisan 

D.  E.  Prazier 


Engineering  Aids 


F.  L.  Firebaugii 
E.  H.  Ford 
C.  W.  Frazier 
George  Garlinghouse 
C.  R.  Hagberg 

C.  A.  Harper 
Leslie  Helgesson 

D.  J.  Stout  . 
J.  G.  Meyer 
W,  J.  Feeney 
S.  E.  Perkins 


E.  R.    HiNNANT 

G.  R.  King 

F.  Montealegke 
Cleo  C.  Osborne 
D.  G.  Spellman 
Dewey  Turner 

G.  Zucco 
H.   Neuman 
R.  H.  Wight 
W.  L.  Pease 


( 9  ) 


LIST  OF  PLATES 


Plate  No.                                                                                                                                       Paoe 
I.   "Hydrographs  of  Year  of  Greatest  Recorded  Flood", 16 

II.   "Probable   Frequency   of   Flood   Discharge" 21 

III.  "Plot  of  All  Floods  of  Record — Years  Superimposed" 28 

IV.  "Relation  of  Time  of  Year  to  Flood  Occurrence" — Sacramento  and  San 

Gabriel    Rivers 30 

V.   Same — Mokelumne  and  San  Joaquin  Rivers 32 

VI.   "I'rogressive  Rainfall  Index  at  Time  of  Flood  Flow" 42 

VII.  "Relation  of  Progressive  Rainfall  Index  to  Flood  Occurrence" — Sacra- 
mento and  San  Gabriel  Rivers 44 

VIII.  Same — Mokelumne   River 45 

IX.   Same — San  Joaquin  River 46 

X.   "Reservoir    Space   Required    to    Control   Floods" — Sacramento    and    San 

Gabriel   Rivers - 55 

XI.   Same — Mokelumne    River 56 

XII.   Same — San  Joaquin  River 57 

XIII.  "Relation  of  Time  of  Year   to  Need  of  Reservoir   Space" — Sacramento 

and  San  Gabriel  Rivers 63 

XIV.  Same — Mokelumne  and  San  Joaquin  Rivers 64 

XV.   "Relation  of  Progressive  Rainfall  Index  to  Need  of  Reservoir  Space" — 

Sacramento  and   San   Gabriel  Rivers 65 

XVI.   Same — Mokelumne    River 66 

XVII.   Same — San   Joaquin  River 67 

XVIII.  "Reservoir  Operating  Diagram  for  Controlling  Floods  on  Sacramento 
River — ^Maximum  Controlled  Flow  Near  Red  Bluff — 125,000  Second- 
Feet"    , 76 

XIX.  "Reservoir  Operating  Diagram  for  Controlling  Floods  on  Mokelumne 
River — Maximum  Controlled  Flow  Near  Clements — Rain-Water 
Floods  5,300  Second-Feet,  Snow-Water  Floods  7,100  Second-Feet__     SO 

XX.  "Reservoir  Operating  Diagram  for  Controlling  Floods  on  the  San 
Joaquin  River — Maximum  Controlled  Flow  Near  Friant — Rain- 
AVater  Floods  10,700  Second-Feet,  Snow-Water  Floods  14,200 
Second-Feet"    84 

XXI.   "Reservoir  Operating  Diagram   for  Controlling  Floods  on   San   Gabriel 

River — Maximum  Controlled  Flow  Near  Azusa  1,900  Second-Feet"      SS 

XXII.    "I'erformance   of  Reservoir   Operating  Diagrams   in  Controlling  Floods 

of   Record" 96 

XX II I.  "lOffect  of  Controlling  Sacramento  River  Floods  Upon  Stage  of  Kennett 

Reservoir"     . 101 

XXIV.  "Effect  of  Controlling  Mokelumne  River  Floods  Upon  Stage  of  Pardee 

Reservoir"     119 

XXV.   "Effect  of  Controlling  San  Joaquin  River  Floods  Upon   Stage  of  Tem- 

jierance  Flat  Rservoir" 131 

^  XXVI.   "Effect   of   Controlling    San    Gabriel    River   Floods   Upon    Stage   of   San 

Gabriel  Reservoir" 151 

XXVII.   "Performance  of  Reservoir  Operating  Diagram  in  Controlling  Floods  of 

Record  Coordinalely  with   Conservation" 205 

XXVIII.  "Effect  of  Omission  of  the  First  Half  of  the  Years  of  Record  that  Con- 
tain Five  of  the  Largest  Floods  on  Indicated  Reservoir  Space 
Required  to  Control  Flf)ods  on  Sacra;npnto  River  Nenr  Red  Bluff"_    212 

(  10  ) 


i 


LIST  OF  TABLES 


YEARLY    SUMMARIES    OF    RESERVOIR    YIELDS    COMPUTED    ON     A 

DAILY    BASIS 
Table  No.  Page 

1.  Kennett  Reservoir  on  Sacramento  River — Water  and  Power  Yield,  Operating 

Primarily  for  Power  Generation  With  Incidental  Irrigation  Both  With 
and  Without  Flood  Control  by  Reservoir  Operating  Diagram 108 

2.  Same — Water  and  Power  Yield,  Operating  Primarily  for  Irrigation  With  Inci- 

dental   Power   Generation    Both   With    and   Without   Flood    Control    by 
Reservoir  Operating  Diagram 110 

3.  Same — Comparison   of  AVater  Yield,   Operating  Primarily  for   Irrigation  for 

Two  Methods  of  Flood  Control 112 

4.  Same — Comparison    of    Water    and    Power    Yield,    Operating    Primarily    for 

Power  Generation  With  Incidental  Irrigation  for  Two  Methods  of  Flood 
Control     114 

5.  Same — Summary  of  Power  Yield  by  Years  Both  AVith  and  Without  Flood 

Control    116 

6.  Pardee  Reservoir  on  Mokelumne  River — Water  and  Power  Yield  Both  With 

and  Without  Flood  Control  by  Reservoir  Operating  Diagram 124 

7.  Same — Comparison   of  Water  and   Power  Yield   for  Two   Methods  of  Flood 

Control    12(i 

8.  Same — Summary    of    Water    and    Power    Yield    by    Years    Both    With    and 

Without  Flood  Control 128 

9.  Temperance  Flat  Reservoir  on  San  Joaquin  River — Water  and  Power  Yield 

E'oth  With  and  Without  Flood  Control  by  Reservoir  Operating  Diagram   134 

10.  Same — Comparison   of  Water  and   Power  Yield  for   Two  Methods  of  Flood 

Control    136 

11.  Same— Summary  of  Water  and  Power  Yield  by  Years  Both  With  and  AVith- 

out    Flood    Control 13S 

12.  San   Gabriel  Reservoir  on   San   Gabriel  River — AA'ater  Yield   Under   "Coordi- 

nated Plan,"  Flood  Control  and  Seasonal  Storage  Coordinated 158 

13.  Same — AA'ater  Yield  Under  "Coordinated  Plan,"  Flood  Control,  Seasonal  and 

Over-year    Storage    Coordinated 160 

14.  Same — Average  Size  of  Flows  of  Water  Yield  Under  "Coordinated  Plan"__   162 

15.  Same — Comparison  of  Water  Yield  for  Two  Methods  of  Flood  Control  Coordi- 

nated With  Seasonal  and  Over-year  Storage 180 

16.  Same — Comparison  of  AVater  Yield  for  Three  Steps  in  Coordinating  the  Use 

of  Reservoir  Space . 182 

17.  Same — Comparison  of  Water  Yield  for  Two  Sizes  of  Reservoir  Operating  for 

Flood  Control  and  for  Constant  Draft  Only 184 

18.  Same — Average   Size   of  Flows   of  Water  Yield   for   Three    Steps   in   Coordi- 

nating the  Use  of  Reservoir  Space 186 


(11) 


LIST  OF  TABLES— Continued 


MONTHLY    SUMMARIES    OF    RESERVOIR    YIELDS    COMPUTED    ON    A 

DAILY    BASIS 
Tablp:  No.  ^'a^^^ 

la.  Kennett  Reservoir  on  Sacramento  River — AVater  and  Power  Yield,  Operat- 
ing Primarily  for  Power  Generation  With  Incidental  Irrigation  Both 
With  and  Without  Flood  Control  by  Reservoir  Operating  Diagram.-  218 

2a.  Same — Water  and  Power  Yield,  Operating  Primarily  for  Irrigation  AVith 
Incidental  Power  Generation  Both  With  and  Without  Flood  Control 
by   Reservoir   Operating  Diagram 234 

3a.   Same — Comparison    of    Water    Yield,    Operating    Primarily    for    Irrigation 

for  Two  Methods  of  Flood  Control 250 

4a.  Same — Comparison  of  Water  and  Power  Yield,  Operating  Primarily  for 
Power  Generation  With  Incidental  Irrigation  for  Two  Methods  of 
Flood    Control 266 

5a.  Same — Summary  of  Power  Yield  by  Months  Both  With  and  Without  Flood 

Control    282 

6a.  Pardee  Reservoir  on  Mokelumne  River — ^Water  and  Power  Yield  Both  With 

and  Without  Flood  Control  by  Reservoir  Operating  Diagram 300 

7a.   Same — Comparison  of  Water  and  I'ower  Yield   fur  Two  Months  of  Flood 

Control    :<12 

Sa.  Same — Summary  of  Water  and   Power  Yield  by   Months  Both  With   and 

Without  Flood  Control ?'2« 

Oa.  Temperance  Flat  Reservoir  on  San  .Toaquin  River — Water  and  Power  Yield 

Both  With  and  Without  Flood  Control  by  Reservoir  Operating  Diagram  332 

10a.   Same — Comparison  of  Water  and  Power  Yield  for  Two  Methods  of  Flood 

Control    342 

11a.   Same — Summary   of  Water   and   Power   Yield   by   Months   Both   With    and 

Without  Flood  Control 352 

12a.   San  Gabriel  Reservoir  on  San  Gabriel  River — Water  Yield  Under  "Coordi- 
nated Plan,"  Flood  Control  and  Seasonal  Storage  Coordinated 3G0 

13a.   Same — Water  Yield  Under  "Coordinated  Plan,"  Flood  Control,  Seasonal  and 

Over-year   Storage   Coordinated 382 

15a.   Saine — Comparison    of   Water   Yield    for    Two    Methods    of    Flood    Control, 

Coordinated  With  Seasonal  and  Over-year  Storage 4  04 

16a.   Same — Comparison  of  Water  Yield  for  Three  Steps  in  Coordinating  the  ITse 

of  Reservoir  Space 426 

17a.  Same — Comparison  of  Water  Yield  for  Two  Sizes  of  Reservoir  Operating 

for  Flood  Control  and  Constant  Draft  Only 448 


(  12  ) 


CHAPTER  I. 


OPPORTUNITY  FOR  CONTROLLING  FLOODS  BY  RESERVOIRS. 


Past  consideration   given  to  control   of  floods  by   reservoirs. 

The  control  of  floods  by  reservoirs  has  been  regarded  in  the  past, 
generally,  as  an  nueconomic  system  of  protection.  However,  knowl- 
edge of  reservoir  sites  in  California  and  of  the  extent  to  which  they 
will  have  to  be  employed  in  order  that  the  State's  latent  resonrces  may 
be  utilized,  is  comparatively  recent.  The  report  of  the  Con.servation 
Commission*  of  1912,  although  mentioning  the  necessity  of  storage, 
does  not  list  more  than  a  couple  of  dozen  reservoir  sites.  Not  until 
the  water  resources  investigations  were  initiated  in  1921  has  there 
been  general  public  knowledge  of  the  part  reservoirs  will  play  in  the 
future  development  of  this  state.  It  has  been  pointed  out  in  this 
work,  that  a  construction  program  adequate  for  tlie  State's  poten- 
tialities will  eventually  total  50,000,000  acre-feet  or  more  of  reservoir 
capacity.  This  will  involve  the  construction  of  several  hundred  large 
reservoirs.  More  than  a  thousand  sites  are  now  known  to  exist,  more 
than  will  be  required  for  a  complete  development  of  available  waters. 

Such  study  as  has  been  given  previously  to  the  control  of  floods  by 
reservoirs  indicates  that  their  cost,  when  constructed  for  flood  control 
purposes  alone,  exceeds  so  far  the  cost  of  equivalent  protection  by 
leveed  channels  and  by-passes,  that  only  in  instances  of  unusually  cheap 
construction  or  in  the  vicinity  of  metropolitan  areas  of  high  property 
values,  can  reservoirs  be  utilized  for  flood  control  purposes.  In  all 
these  studies,  either  the  entire  space  in  the  reservoir  or  some  fraction 
of  it,  has  been  allotted  to  flood  control  for  use  only  in  the  temporary, 
detention  of  flood  flows  and  to  be  held  empty  at  all  times  other  than 
during  large  floods.  Under  this  mode  of  operation,  the  entire  cost  of 
the  storage  space  allotted  to  flood  control  is  chargeable  to  the  protective 
system.  Because  this  required  space  is  large  on  important  streams, 
the  cost  of  flood  control  by  reservoirs  usually  has  been  found  pro- 
hibitive. The  only  instances  of  reservoir  construction  for  flood  control 
purposes  in  California  are  the  current  undertakings  of  the  Los  Angeles 
County  Flood  Control  District  and  of  the  City  of  Stockton.  In  both  of 
these  instances  bonds  have  been  voted.  Several  reservoirs  have  been 
constructed  by  the  Los  Angeles  District. 

It  has  been  considered  by  some,  without  much  study,  that  the  con- 
struction of  large  reservoirs  for  irrigation  and  power  purposes  will 
diminish  the  size  of  floods.  A  careful  analysis,  however,  discloses  that, 
unless  tliese  reservoirs  are  operated  especially  for  flood  control  pur- 
]ioses.  they  are  apt  to  be  fairly  well  filled  upon  the  arrival  of  large 
floods,  because  large  floods  do  not  occur  in  seasons  of  small  run-off. 
While  they  may  absorb  many  medium  and  small  floods,  de])endence  can 
not  be  placed  upon  their  absorption  of  large  floods.  Therefore  the  va.st 
program  of  reservoir  construction  that  will  be  necessary  for  domestic 
supply,   irrigation  and   power,  has  no  particular  bearing  upon  flood 

*  The  State  Conservation  Commission  was  appointed  in  1911  to  investigate  and 
report,  among  other  things,  on  water,  the  use  of  water,  water  power,  irrigation  and 
reclamation. 

(  13  ) 


14  WATEli    RESOURCES   OF   CALIKORNIA. 

control,  unless  a  special  program  is  devised  for  its  employment  for  this 
purpose. 

That  the  engineering  profession  has  held  the  belief  that  reservoirs 
would  come  into  more  general  use  in  controlling  floods,  is  shown  by  the 
report  of  the  California  Debris  Commission  of  June  29,  1911.  The 
report  of  this  commission  is  one  of  the  most  extended  studies  of  flood 
control  that  has  been  made  in  California.  The  plan  of  leveed  channels 
i.nd  by-passes  for  carrying  off  maximum  flood  flows  proposed  in  this 
report  was  adopted  by  both  the  California  Legislature  and  the  National 
Congress  and  is  being  followed  in  reclaiming  a  million  acres  of  overflow 
laud  in  the  Sacramento  Valley.  The  works  are  now  two-thirds  com- 
])lete.  In  planning  and  recommending  the  coiistruction  of  these  works, 
eousideration  was  given  by  the  California  Debris  Commission  to  the 
1  eduction  of  floods  by  reservoirs.  Its  conclusions  were  expressed  in 
the  1911  report  as  follows: 

"While  favoring  the  use  of  reservoirs  as  far  as  possible,  and  considering  that 
one  of  the  advantages  of  the  project  herein  proposed  is  that  it  lends  itself 
to  future  storage  possibilities,  tlie  conimi.ssion  believes  that  it  is  not  economical 
to  construct  reservoirs  for  flood  control,  but  that  such  construction  should  be 
deferred  until  these  resorvoii-s  prove  desirable  for  power  and  irrigation 
purposes." 

Future   conditions  favorable   for   use    of   reservoirs    in   controlling   floods. 

The  time  has  arrived  when  reservoir  construction  is  necessary  for 
both  power  and  irrigation  purposes.  California  now  stands  with  a  full 
measure  of  development  of  the  summer  flow  in  its  streams.  Further 
progress  involves  the  storage  of  winter  and  spring  storm  water  and  its 
I'etention  for  summer  use.  The  employment  of  these  reservoirs  for 
flood  control,  that  necessarily  will  be  constructed  in  succeeding  years 
for  irrigation,  power  and  domestic  suj^plies,  is  a  matter  of  great  public 
interest.  Its  accomplishment  would  be  of  inestimable  public  benefit. 
The  water  resources  investigation,  therefore,  has  undertaken  the  inten- 
sive study  of  the  problem  of  how  flood  control  might  benefit  from  the 
construction  of  reservoirs  for  other  purposes. 

The  attempt  to  use  reservoirs  for  both  flood  control  and  conservation 
seems  at  first  like  a  contradictor}'  effort.  To  be  useful  for  regulating 
floods,  reservoirs  should  be  held  empty  during  the  period  of  heavy 
run-off'  in  order  to  be  able  to  absoi-b  an  excessive  flood  flow  if  it  should 
occur,  while  for  conservation  purposes,  they  .should  be  allowed  to  fill 
during  this  same  period  in  order  that  the  run-oft'  season  may  end  with 
a  full  reservoir.  However,  a  detailed  analysis  of  the  tinu'  of  occurrence 
and  volume  of  flood  flows  discloses  a  procedure  for  filling  reservoirs 
that  will  hold  in  reserve  sufficient  cai)acity  to  absorb  floods  during  the 
time  in  which  they  are  likely  to  occur,  and  progressively  release  this 
space  for  filling  as  the  end  of  the  flood  season  approaches.  This  bulletin 
is  devoted  to  the  j)resentation  of  these  nuitters. 

Physical     opportunity     to     combine     conservation     and     flood     control     in     same 
reservoir. 

That  a  combination  i)rogram  of  conservation  and  flood  control  should 
be  possible  seems  evident  from  an  examination  of  the  hydrographs  of 
California  streams.  This  discloses  that  excessive  rates  of  flood  flow  arr- 
of  comparatively  short  duration,  that  they  occur  in  the  middle  or  fore 


THE    CONTROL    OF    FLOODS    BY    KESEKVOIKS.  15 

part  of  the  period  of  heavy  run-oft',  and  that  the  volume  of  water  dis- 
charged at  the  extremely  high  rates  is  relatively  small.  The  reservoir 
capacity  required  to  absorb  these  high  rates  of  flood  flow,  although  large 
in  itself,  is  still  very  much  less  than  will  be  required  to  e(iualize  any 
great  part  of  the  seasonal  run-oft'  for  irrigation  use.  These  general 
observations  are  illustrated  by  the  hydrographs  of  four  typical  streams, 
the  Sacramento,  Mokelumne,  San  Joaquin  and  San  Gabriel  rivers, 
drafted  on  Plate  I,  "  PIvdrographs  of  Year  of  Greatest  Recorded 
Flood."* 

On  this  plate,  full-line  hydrographs  portray  the  run-oft'  tlirougliout 
tlie  year  of  the  greatest  flood  on  record  on  each  of  the  four  streams.  A 
heavy  horizontal  line  crosses  each  hj^drograph  plotted  at  half  the  rate  of 
discharge  of  a  large  flood  which  is  here  taken  as  one  estimated  to  be 
exceeded  at  average  intervals  of  25  years.  (The  frequency  of  flood 
occurrence  is  taken  up  in  detail  in  the  second  chapter. )  The  areas  within 
the  full-line  hydrographs  above  the  heavy  horizontal  line,  shaded  in  solid 
black,  represent  the  total  volume  of  water  that  would  have  had  to  be 
detained  by  reservoirs  in  that  season  in  order  to  limit  the  downstream 
flow  to  half  the  rate  of  a  once-in-25-year  flood.  Superimposed  on  these 
full-line  hydrographs  of  the  flood  years  are  hydrographs  of  seasons  of 
normal  run-oft'  shown  by  dotted  lines.  The  cross-hatched  areas  within 
these  dotted-line  hydrographs  represent  the  volume  of  winter  and 
spring  run-off  that  would  have  to  be  stored  to  make  the  entire  run-off 
of  a  normal  season  available  for  irrigation  use.  A  comparison  of  the 
solid  black  with  the  cross-hatched  area  on  each  figure  of  Plate  I,  shows 
the  relative  reservoir  capacity  needed  to  limit  the  largest  flood  of  record 
to  half  the  rate  of  a  once-in-25-year  flood  and  to  equalize  the  entire 
run-off  of  a  normal  season  for  irrigation  use.  It  may  be  observed  that 
the  reservoir  capacity  required  to  cut  large  flood  flows  in  half  is  small 
compared  to  that  required  to  equalize  the  entire  run-off  of  a  normal 
season  for  irrigation  use.  On  the  Sacramento,  Mokelumne  and  San 
Joaquin  rivers  the  one  is  from  5  to  15  times  larger  than  the  other,  while 
on  the  San  Gabriel,  a  very  flashy  stream,  the  reservoir  capacity  required 
to  equalize  the  entire  run-oft'  of  a  normal  season  for  irrigation  purposes 
is  about  twice  that  needed  to  absorb  the  top  half  of  a  large  flood.  Since 
it  will  be  necessary  in  coming  years,  on  most  of  the  streams  of  the  State, 
to  make  the  entire  flow  of  normal  years  available  for  use  in  order  that 
deficient  w^ater  supply  may  not  limit  the  growth  of  California,  it  is  seen 
that  the  reservoir  cai)acity  necessary  for  conservation  i)ur]>oses  is  very 
much  greater  than  that  needed  to  limit  the  high  rates  of  flood  flow  to 
half  that  of  a  once-in-25-year  flood,  excejit  on  streams  like  the  San 
Gabriel  River  that  have  exceedingly  flashy  run-off.  Any  reservoir  or 
group  of  reservoirs  that  have  sufficient  capacity  to  store  a  considerable 
fraction  of  the  winter  and  spring  run-oft'  of  a  normal  year,  if  not 
already  well  filled,  could  easily  al)sorl)  the  volume  of  flood  water  wliich 

*  Water  Supply  Paper  No.  551  of  the  United  States  Geolog-ical  Survey,  recently 
published,  places  the  maximum  di.scharg-e  of  the  Mokelumne  River  at  Clements  at 
25,500  second  feet.  This  is  obtained  by  applying  the  rating  curve  of  the  1911  flood 
to  the  gage  heights  of  1907.  The  crest  discharge  of  the  1907  flood  has  been  pub- 
lished as  17,000  second  feet  in  foriner  publications  including  Water  Supply  Paper 
No.  299  in  which  are  printed  the  daily  discharges  of  the  19  07  flood.  The  figures 
contained  in  Water  Supply  Paper  No.  299  have  been  used  in  preparing  this  volume. 
Should  the  daily  discharges  of  the  1907  flood  be  revised  by  application  of  the  1907 
gage  heights  to  the  1911  rating  curve,  the  increase  in  their  values  would  be  so  sub- 
stantial as  to  require  a  complete  revision  of  the  analyses  of  floods  on  the  Mokelumne 
River  contained  in  this  volume  in  order  to  make  the  analyses  liarmonize  with  the 
increased   discharge  values. 


16 


WATER   RESOURCES   OF   CALIFORNIA. 


[>LATE    I. 


SACRAMENTO  RIVER  NEAR  RED  BLUFF 

1908-1909  


MAR. 


APRIL   i     MAY 


RESERVOIR  SPACE  REQUIRED 
I.  To  absorb  flows  in  excess  of 
half  rtie  maximum  flood  rate. 
2. To  make  the  run-off  of  a  normal 
>ear available  for  irrigation. 


JUNE       JULY        AUG. 


/  Irrigation  draft  equal  lo  normal  mn-off 


MOKELUMNE   RIVER    NEAR    CLEMENTS 
I9I0-I9II 


(A 

C 
fU 
V) 

o 


SEPT. 


OCT. 


NOV. 


DEC. 


JAN. 


FEB.        MAR.     APRIL       MAY 


JUNE 


JULY 


AUG. 


50%  of  24 hour  average 
of  once-in-253iear  flooi 


6- 

4- 

Year  of  normal  run-off  (1921-1922 


-RESERVOIR  SPACE  REQUIRED 

.^'l.  To  absorb  flows  m  excess  of 

■^      half  the  maximum  flood  rate. 

2.  To  make  the  run-off  of  a  normal 

^ear available  for  irrigation. 


:2E^=i: 


SAN    JOAQUIN    RIVER    NEAR   FRIANT 

1910  -1911 


SAN    GABRIEL  RIVER   NEAR    AZUSA 
1915  -  1916 


OCT. 


NOV. 


DEC. 


APRIL 


AUG. 


■RESERVOIR  SPACE  REQUIRED 
-. — -I.  To  absorb  flows  in  excess  of 
half  the  maximum  flood  rate. 
2.  To  make  the  run-off  of  a  nomal 
.jfear available  for  irrigation. 


Hydrographs  of  Year  of  GREAitr'  Rlcorded  Flood 


THE    CONTROL    OP    FLOODS    BY    RESERVOIRS.  17 

otherwise  would  be  discharged  at  rates  in  excess  of  half  that  of  a  once- 
in-25-year  flood. 

Although  the  volume  of  flood  water  discharged  at  rates  in  excess  of 
half  that  of  a  large  flood  is  relatively  small,  an  inspection  of  the  gen- 
eral shape  of  the  hydrographs  on  Plate  I  reveals  that  the  volume  of 
flood  water  discharging  at  rates  less  than  half  that  of  a  large  flood 
increases  quite  rapidly  with  the  lower  rates  of  discharge.  This  is  indi- 
cated by  the  increasingly  greater  widths  of  the  peaks  on  the  hydro- 
graphs  as  they  descend  below  the  heavy  horizontal  lines  drawn  at  rates 
half  that  of  a  once-in-25-year  flood.  At  about  the  quarter  points,  except 
on  the  San  Gabriel  River,  these  peaks  merge  more  or  less  into  one 
another  on  account  of  their  increasing  wddth.  This  greater  width  of 
the  peaks  on  the  hydrographs  represents  increasing  duration  of  flow  at 
the  lower  rates. 

The  flows  delineated  by  the  thin  width  of  the  peaks  on  their  upper 
part  are  high  rates  of  discharge,  the  direct  result  of  intense  rainfall 
on  saturated  or  snow-covered  areas.  Since  high  rates  of  rainfall  do 
not  continue  over  long  periods  of  time,  the  duration  of  these  exces- 
sively large  rates  of  run-off  is  brief  and  the  peaks  on  the  hydrographs 
have  a  narrow  width.  As  lesser  flows  are  considered,  the  run-off  from 
medium  and  low  rates  of  rainfall,  which  continue  much  longer,  as  well 
as  the  tardy  waters  draining  oft'  the  catchment  area  in  the  wake  of 
heavy  storms,  are  included  to  a  greater  extent  and  the  peaks  on  the 
hydrographs  have  a  greater  width.  The  duration  of  the  lower  rates 
of  rainfall  is  so  much  longer  than  the  duration  of  the  higher  rates 
that  much  greater  volumes  of  water  would  have  to  be  detained  by 
reservoirs  if  floods  were  to  be  reduced  to  as  much  as  a  quarter  or  less 
of  the  rate  of  a  large  flood  than  to  only  a  half. 

A  further  increase  in  the  volume  of  water  that  would  have  to  be 
detained  in  order  to  limit  flood  flows  to  much  less  than  half  that  of  a 
once-in-25-year  flood  comes  from  melting  snow  on  those  streams  a  con- 
siderable part  of  whose  drainage  areas  extends  into  high  altitudes.  As 
illustrated  by  the  hydrographs  of  the  Mokelumne  and  San  Joaquin  on 
Plate  I,  fairly  high  rates  of  discharge  occur  from  melting  snow  during 
May,  June  and  July.  The  Sacramento  and  the  San  Gabriel,  the  two 
other  illustrative  streams,  do  not  have  snow-water  floods.  Unlike  the 
flood  discharge  from  rainfall,  that  from  melting  snow  continues  over 
rather  long  periods  of  time.  However,  their  greatest  rate  seldom 
exceeds  half  that  of  a  once-in-25-year  flood,  so  that  they  concern  flood 
control  only  if  floods  are  to  be  reduced  to  less  than  this  rate  of  flow. 

While  the  foregoing  considerations  are  very  general  and  are  prin- 
cipally illustrative  of  the  characteristics  of  stream  flow  to  be  analyzed 
in  detail  in  later  chapters,  nevertheless,  they  indicate  that  the  volume  of 
water  to  be  detained  by  reservoirs  would  increase  very  rapidly  if  an 
attempt  were  made  to  reduce  floods  to  much  less  than  half  a  onee-in-25- 
vear  flood.  The  capacity  required  to  do  this  would  be  much  larger 
than  probably  will  be  constructed  on  most  of  the  State's  streams  for 
many  years  to  come.  The  relatively  small  space  required  to  reduce 
floods  to  half  the  rate  of  a  once-in-25-year  flood  or  thereabouts  makes 
it  appear,  in  general,  that  this  would  be  the  possible  present  utility  of 
conservation  reservoirs  for  controlling  floods.  A  coordinated  program 
of  operation  for  both  conservation  and  flood  control  would  be  necessary 
for  this  accomplishment. 

2—52411 


18  WATER    JtESOUUCES    OF    CALIFORNIA. 

CHAPTER  II. 


SYSTEMS  OF  FLOOD  CONTROL. 


Leveed  channel  system. 

There  are,  in  general,  two  systems  of  flood  control:  one  tliat  leads 
flood  flows  to  the  ocean  in  si)ecially  i)repared  channels  without  diminu- 
tion in  vohuue,  the  other  that  reduces  the  volume  of  flow  to  a  harndess 
amount  by  detention  of  excess  watei*  in  storage  reservoirs.  The  first  is 
the  system  in  common  use,  for  it  is  usually  least  in  cost.  The  reasonable 
cost  of  this  system  is  attained  by  constructing  the  greater  part  of  the 
flood  channels  above  the  ground  surface.  The  banks  of  the  channels 
are  formed  by  earthen  levees  excavated  from  adjacent  borrow  pits. 
The  capacity  of  the  channels  is  fixed  by  the  spacing  and  height  of  the 
levees.  Seldom  does  the  borrow  pit  from  which  the  levee  material  is 
excavated  constitute  a  very  large  part  of  the  waterway.  Even  Avhere 
the  leveed  channels  follow  natural  water  courses,  their  increased 
capacity,  due  to  the  construction  of  the  levees,  is  largely  in  the  cross- 
sectional  area  above  the  ground  surface.  Thus,  the  safety  of  the  system 
fests  upon  the  strength  of  the  levees  to  withstand  the  water  ])ressure 
and  the  sufficiency  of  the  carrying  capacity  of  the  flood  channels. 
Should  the  levees  fail  or  be  breached  by  over-topping,  a  large  part  of 
the  entire  flood  volume  might  run  through  the  breach  over  the  adjacent 
land. 

One  of  the  })rineipal  reasons  for  success  in  this  system  of  protection  is 
the  infrequent  occurrence  and  short  duration  of  large  floods  that  tax  the 
strength  of  the  levees  and  the  capacity  of  the  channels.  On  the  other 
hand,  one  of  the  principal  dangers  in  this  system  is  the  neglect  of 
maintenance  of  the  levees  and  channels  through  a  false  sense  of  security 
that  develops  during  the  ten-or-more-jear  average  intervals  between 
large  floods.  The  levees  that  form  the  channel  banks  may  settle,  crack 
or  be  holed  by  burrowing  animals  during  the  long  periods  of  only 
l)artial  use.  Also,  the  channel  ca])acity  may  deteriorate  through  the 
growth  of  trees,  brush  or  tule  or  the  deposit  of  silt  by  the  le.sser  floods. 
The  intermittent'  wettiaigs  from  smaller  floods  encourage  channel 
growths.  The  usually  fertile  soil  and  the  favorable  moisture  conditions 
on  the  low  land  thai  Hood  channels  naturally  oeeu])y  often  produce 
obstructive  growths  that  occupy  considerable  ])arts  of  the  waterway 
areas.  The  nuiinteiuiiu'e  of  these  channels  in  coiulition  to  .safely  carry 
off  the  infrequently  occurring  lai-ge  floods  n'(piires  constant  attention 
and  very  considerable  expense. 

Reservoir  system. 

The  second  system  of  Hood  coiitroi,  tliat  which  reduces  the  volume  of 
flood  flow  by  detention  of  excess  water  in  storage  reservoirs,  is  a  recent 
innovation  in  (*alifoi-nia.  The  Los  Angeles  County  Flood  Control  Dis- 
trict now  has  a  i|i40.0()0,()()()  program  under  way.  This  provides  for  the 
construction  of  thirteen  reservoirs  for  flood  control  purposes  on  Tios 
Angeles  County  streams.  The  City  of  Stockton  has  undertaken  the 
consti-uction    of   a   reservoir   on   the   Calaveras   River  solely   for   flood 


THE    CONTROL    OF    FLOODS   BY    RESERVOIRS.  19 

control  purposes.  The  reservoir  system  has  been  adopted  in  these 
instances  because  tlie  high  property  values  and  close  settlement  of 
some  of  the  territory  protected  permits  greater  expenditures  than  have 
been  customary  in  the  past. 

Tlie  high  cost  of  constructing  reservoirs  for  flood  control  alone  and 
the  large  size  required  to  reduce  floods  to  harmless  amounts  limits  the 
usefulness  of  the  reservoir  system  of  protection.  To  be  effective  with 
certainty,  liberal  reservoir  capacity  has  to  be  provided  and  the  rules 
of  operation  rigidly  adhered  to  so  that  this  s]iace  will  surely  be  em])ty 
at  the  time  needed  for  detaining  flood  waters.  The  system  is  attractive, 
however,  where  the  cost  is  justified,  because  of  tlie  shorter  traffic  cross- 
ings on  the  smaller  channels  needed,  the  elimination  of  the  bother  and 
expense  of  maintaining  large  Avaterways  in  expectancy  of  a  great  flood 
through  years  of  use  to  but  a  small  part  of  their  total  capacity,  and 
the  possiijility  of  utilizing  areas  that  would  otherwise  be  occupied  by 
flood  channels. 

Combined   reservoir  and   leveed   channel   system. 

It  was  pointed  out  in  the  first  chapter  that  there  is  a  physical  op]ior- 
tunity  to  obtain  joint  use  of  the  same  space  in  reservoirs  for  botli  con- 
servation and  flood  control  purposes.  It  was  pointed  out  also  that  the 
present  possibility  for  economical  joint  use  of  the  same  reservoir  space 
will,  in  general,  be  limited  to  a  reduction  of  flood  flows  to  a  half  or  a 
third  of  that  of  a  large  flood.  On  many  streams  in  California,  leveed 
channels  will  be  recpiired  to  carry  off  even  a  half  or  a  third  the  volume 
of  a  large  flood,  although,  of  course,  the  size  of  these  channels  need  not 
be  nearly  as  large.  Therefore,  leveed  channels  will  ])robably  remain 
l)art  of  most  of  our  flood  protection  systems  until  either  the  close  settle- 
ment of  the  overflow  areas  warrants  the  great  expense  of  their  com- 
])lete  elimination,  or  the  demand  for  additional  water  supplies  forces 
the  constructioii  of  much  greater  reservoir  capacity  than  will  be 
required  for  a  good  many  years  at  the  present  rate  of  growth.  Thus, 
the  combination  of  the  reservoir  and  the  leveed  channel  system  of  pro- 
tection will  probably  be  most  suitable  to  conditions  on  many  California 
streams  for  some  time  to  come. 

The  suitability  of  the  combined  system  to  the  immediate  future  is 
fortunate,  because  often  much  of  the  work  first  constructed  under  the 
leveed  channel  system  may  be  utilized  in  the  combined  system  to  afford 
an  increased  degree  of  protection.  Also,  the  combined  system  of  pro- 
tection removes  the  most  unsatisfactory  features  of  the  leveed  channel 
system.  In  California,  the  leveed  channels  take  up  much  room  and 
form  awkward  obstacles  to  traf^c  and  communication.  This  public 
inconvenience  rapidly  gains  importance  as  territory  becomes  more 
thickly  populated.  The  cost  of  bridges  alone  over  wide  channels  is  a 
large  item  of  expense  and  increases  greatly  as  denser  population 
demands  more  convenient  routes  of  communication. 

In  southern  California,  whose  rapid  growth  has  already  brought 
20  per  cent  of  available  flat  lands  into  incorporated  cities  and  towns, 
and  where  their  extent  is  limited,  the  occupation  of  large  areas  by  flood 
channels  is  a  serious  impediment  to  community  exi)ansion.  Although 
tlie  extent  of  flat  lands  is  greater  in  northern  California,  the  area 
occupied  by  flood  channels  is  nevertheless  a  considerable  item   in  the 


20  WATER   RESOURCES   OK    OAIjIFORNIA. 

inventory  of  lands  favorable  for  intensive  human  occupation.  One 
of  the  channels  of  the  flood  control  project  in  the  Sacramento  Valley 
is  as  much  as  three  miles  in  width,  and  in  total  all  the  channels  of  this 
project  occupy  250  square  miles  of  territory  that  can  be  put  to  only 
partial  use. 

The  channels  of  the  combined  system  would  be  of  moderate  size  and 
capacity.  Such  channels  could  be  more  easily  maintained,  both  because 
they  woiild  be  smaller  in  size  and  because  a  larger  part  of  their  total 
capacity  would  be  used  oftener.  The  elimination  by  reservoir  control 
of  the  excessively  high  rates  of  run-ott'  that  are  particularly  dangerous 
by  surcharging;  the  present  large  channels  at  very  infrequent  intervals 
would  add  to  the  safety  of  occui)ying'  adjacent  lands.  The  smaller 
channels  would  leave  greater  areas  to  be  reclaimed  and  would  not  con- 
stitute unduly  awkward  barriers  to  traffic  and  communication  under 
the  conditions  of  the  near  future.  Thus,  the  coiiibined  reservoir  and 
leveed  channel  .system  of  protection  has  distinct  advantages.  If  a 
satisfactory  prog-ram  could  be  devised  for  the  joint  use  of  the  same 
reservoir  space  for  both  conservation  and  flood  control,  it  will  come 
into  use  on  many  California  stream^s.  On  those  streams  wiiere  leveed 
channels  are  already  constructed,  the  safety  of  protection  would  be 
increased,  and  on  other  streams  the  cost  of  building  the  leveed  chan- 
)iels  would  be  reduced.     All  localities  would  be  benefited. 

The  Sacramento  Valley  has  progressed  further  than  any  other  sec- 
tion of  California  in  perfecting-  a  leveed  channel  system  of  flood  i^ro- 
tection.  Here  a  very  extensive  program  is  about  two-thirds  complete. 
The  levees  along-  the  main  river  channel  ai-e  constructed  to  grade  and 
cross-section  for  i)ractically  the  entire  length  and  a  substantial  part  of 
the  larg-e  by-])asses  is  already  built.  The  i)rincipal  unfinished  work 
lies  along-  the  tributary  streams.  The  conti-ol  of  floods  by  reservoii's 
could  not  affect  the  works  already  constructed  except  to  increase  their 
elBcienc}^  in  protecting  the  reclaimed  lands.  It  would  reduce  somewhat 
the  volume  of  unfinished  work,  but  the  g:reatest  benefit  would  accrue  by 
the  attainment  of  a  higher  deg:ree  of  protection  than  is  afforded  by  the 
present  system  of  leveed  channels  alone  whose  planned  degree  of  safety 
is  inadequate  foi-  the  intensive  development  and  close  settlement  of  the 
future.  Other  benefits  would  accrue  in  the  reduced  project  main- 
tenance and  in  the  greater  reclaimed  areas  and  shorter  traffic  crossings 
attending-  the  use  of  narrower  channels  than  are  at  i)re.sent  jilanned 
along-  the  tributary  streams.  Thus,  the  combined  reservoir  and  leveed 
channel  system  of  flood  protection  Avould  have  great  value  even  in 
the  Sacramento  Valley,  where  the  leveed  chaniu'l  system  is  lai-gely 
completed. 

Degree  of  protection   in  flood  control  systems. 

In  estimating:  the  future,  while  witnessing  the  present  rapid  growth 
of  i)opulation  and  expansion  in  i)ro])erty  values,  it  would  seem  that 
jiublic  7)olicy  may  recpiire  a  higher  degree  of  ]n-otection  than  present 
economy  would  dictate  in  order  to  ]n'eserve  public  confidence  in  the 
safety  of  residing  and  doing  business  in  areas  subject  to  flood  hazard. 
Prom  this  viewi)oint,  the  degree  of  i>rotection  rendered  by  flood  control 
woi-ks  becomes  an  im|)ortant  subject,  for  about  a  fifth  of  all  the  agri- 
cu1tni-al  area  in  its  natural  condition  is  subject  to  flood  menace. 


THE    CONTROL    OF    FLOODS   BY    RESERVOIRS.  21 

In  examining  the  essential  characteristics  of  the  two  systems  of  flood 
protection,  there  does  not  seem  to  be  any  inherent  difference  in  the 
degree  of  protection  afforded  by  either  one.  Although  there  is  a  danger 
in  transporting  large  volumes  of  water  above  the  ground  surface 
between  parallel  leveees  because  of  the  dependence  for  safety  upon  the 
integrity  of  many  miles  of  earth  dike,  nevertheless  this  system  could  be 
constructed  to  offer  the  same  degree  of  protection  that  is  contained  in  the 
reservoir  system.  The  levees  would  have  to  be  built  with  heavy  cross- 
section  and  protected  on  their  face  from  wave  wash  and  sloughing  and 
the  channels  would  have  to  be  properly  maintained. 

The  degree  of  protection  offered  by  either  system  or  their  combina- 
tion, if  sound  physical  works  are  constructed  with  equal  safety  factors, 
is  essentially  dependent  upon  the  possibility  of  occurrence  of  floods 
greater  than  the  capacity  for  which  the  system  is  designed.  Under 
either  system,  should  a  flood  exceed  the  design  capacity,  the  channels 
■would  be  surchcirged,  with  the  consequent  flooding  of  the  adjacent  lands. 
Inquiry  into  the  possibility  of  occurrence  of  floods  greater  than  the 
design  capacity  of  protective  systems,  therefore,  must  be  the  principal 
feature  of  a  general  discussion  of  the  degree  of  protection  oifered  by 
flood  control  systems. 

Frequency   of  flood   occurrence. 

A  discussion  of  the  occurrence  of  floods  in  California  streams  and 
the  probable  frequency-  with  which  floods  of  various  sizes  might  be 
expected  to  occur  has  been  presented  in  the  1923  report*  on  the  water 
resources  of  the  State.  Here  it  is  shown  that  stream  flow  closely  follows 
the  characteristics  of  precipitation,  the  volume  of  which  is  the  resultant 
of  the  vicissitudes  of  weather  so  complex  that  they  defy  analysis. 

Precipitation  records  show  that  extremely  high  rates  of  rainfall  are 
rather  infrequent  and  invariably  occur  in  the  winter  months  only.  The 
record  at  San  Francisco,**  centrally  located  and  one  of  the  longest  in 
the  State,  shows  that  more  than  four  inches  of  rain  in  twenty-four  hours 
occurred  but  once  in  the  sixty-one  years  of  record,  while  from  three  to 
four  inches  of  rain  in  twenty-four  hours  occurred  nine  times  in  sixty- 
one  years,  from  two  to  three  inches  twenty-nine  times,  and  from  one  to 
two  inches  one  hundred  and  sixty  times.  •  Thus,  it  is  seen  that  the 
highest  rates  of  rainfall  occur  only  at  long  average  intervals  of  time, 
while  the  lower  rates  occur  oftener  and  with  increasing  frequency  as 
the  rate  becomes  less. 

The  duration  of  rainstorms  follows  a  similar  behavior.  The  San 
Francisco  record  shows  that  eight  consecutive  days  of  rain  averaging 
more  than  one  inch  in  twenty-four  hours  occurred  but  four  times  in  the 
sixty-one  years  of  record,  while  it  occurred  for  four  consecutive  days 
twenty-nine  times,  for  three  consecutive  days  fifty-three  times,  two  con- 
secutive days  one  hundred  and  nine  times,  and  one  day  three  hundred 
and  eight  times.  Since  it  is  the  combination  of  extended  storms  and 
high  rates  of  precipitation  that  furnish  flood  run-off,  the  frequency  of 
flood  occurrence  in  the  stream  channels  of  California  may  be  expected 

*  Chap.  V,  Bui.  No.  5,  "Flow  in  California  Streams,"  of  the  Division  of  Engineer- 
ing and  Irrigation.   State  Denartment  of  Public  Works. 

**  U.  S.  Weather  Bureau  Record  1897  to  1926.  Private  Record  of  John  Petee 
1865  to  1897. 


22 


WATKR   RESOURCES   OF    CALIFORNIA. 


PLATE 

I. 

SACRAMENTO   RIVER  NEAR  RED  BLUFF 

I  I  1                  [III! 

TT  TTTT 

M 

,     .                                                  ,    !      ■     '    -    I       ,                           -     ,        • 

1:::: 

■6- id 

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M 

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1   •  "^ 

.     -      i\     \                           1      1 

_ ^-, 

i 

-  ■  t  T  ;  -  -    - :  - 

^^ 

^1^ 

tn  Drainage  Are; 

9,258  sq.mi. 

^T-{ 

1 
1 

tr^ 

m^  " 

k^  1  ' 

:^H — ■    1      1^' 

ood  flow  in  second  feet. 

^,.   -- 

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i^sJ. 

1    , 

j  j 

-1— L- 

I-iii       1— 

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Util— i 

i  n> 

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4000 

.05   . 

n  i  .1 

.2     .5    A 

5.6.7.8:  1            2      s!  4I 

M  M  j 

5  67     10          20  1  S0{40l 

MM 

so  80100 

200  ,300  1  SOO  1^000       2000 

MOKEILUMNE  RIVER  NEAR  CLEMENTS 

1 

1  '  ' 

1 

1 

'i!i 

j    1 

V)    .8=-:  = 

wflfN 

m 

kM 

#= 

i 

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o  yr 

t  '  Dr 

1    1   1  '^ 
ainafe  Arei 

S^2  so. mi. 

H 

^-.44.. 

^ffl 

5^^ 

1 — '■ — i 

1 1 

■  1  — ^ 

1    ' 

jltiplv  by   16,994  to  get 

LI       M 

[ 

,  ■ 

:^  ^' 

1 

■iJ" 

"**^    flood  t  low  in  seconfl  TeeT. 

: 

1 

V 

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lilE 1 

1 

1 

[ 

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::::     ;::o 

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M  1 1 1 
20  |sol4a| 

!^       1  1  i  ■  ri 
80  go  no      200 ;  taa  |  so 

^                                       SAN   JOAQUIN   RIVER   NEAR    FRIANT 

O       5      " 

[ 

[    1 

j 

1 

4-. 

' 

: 

; 

c 

1 

1 

1 

C     1  -- 

—   . !  _j^ 

, 

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1 

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i  1 

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m-^fjr 

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—  £' 

:;:;;jj^ 

^si 

-txtTM— 

J-1Lt_ 

-T-t:r1 : — 

.-_ 

?i 

i^^'    Dr 

aina^e  Area  1531  sq.mi. 
ultipl>  by  43,856  to  get 

-^'1>'N^ 

\" 

.^-..       1 

-L 

13     -  + 

' 

1 

si- 

1 

flood  flow  in  second  feet 

1 

, 

55 

,i... 

_H        ^. 

1      1  1 

4-  np 

II 

^\ 

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07,     .1 

.2     .S  \a 

5.6.7.81  |l 

:       3I4 

5  B!7|  1  10 

1  M  Ml 

20  ho  1  iOl 

'eO  80100 

~l    i  I  11    1 
200  |3DD|  1  50 

1  1% 

1  ' 

2000     ma 

SA^ 

U4.J.  Jii , 

:  r  t : : 

GABR 

EL  RIVER  NEA 

R  AZUSA 

T-^t-f 

P^|-"J^ 

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— 

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1 

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1 

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^-4- 

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; ' ! 

\ 

r 

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111 

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:::       = 

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ralnage  Art 

a  214  sq.mi. 

....      _ 

-^   ^NF 

1 



^  1 

II.  i/i. 

Jltiplv  by    5754   to  ^et 

t                V 

1 

1 

,2  * 

L\ 

1       1 

*^*i    flood  flow  in  second  Teet. 

1 

'  '    ,       ;\kl     ;  Il 

1    ] 

■ 

.  X  1 

1 

.1    :: 

mi 

Dti' 

It™ 

1 

llllllll                                                <■ 

^••tt 

f 

Jl     .              .         S    .4 

frequer 

.5  6   J           1 

icy  witf 

1  which 

5i;7    1)        -^    -  ;-    .-.i.,.,.     ,  ...  :„  ,  ;.g,  ,  ,  .;.: 

values  are  exceeded  in  100  _years 

....      ,   Wtl 

Probable  Frequency  of  Flood  Discharge 

THE    CONTROL    OF    FLOODS    BY    RESERVOIRS.  23 

to  have  characteristics  similar  to  the  frequency  and  dnration  of  the 
higher  rates  of  precipitation. 

An  extended  comparison  of  all  the  stream-gaginp-  records  in  the 
State*  reveals  this  to  be  trne.  Although  this  study  does  not  disclose  the 
sequence  Avitli  which  floods  of  various  sizes  follow  one  another,  it  does 
indicate  that  there  is  a  rather  fixed  relation  between  the  size  of  floods 
and  the  average  interval  of  time  between  their  occurrence.  In  general, 
it  indicates  that,  on  an  average  of  once  in  four  years,  floods  may  occur 
double  or  more  the  size  that  is  exceeded  but  once  a  year ;  that  on  an 
average  of  once  in  twenty  years  floods  may  occur  three  or  more  times 
this  volume ;  that  once  in  two  hundred  years  they  may  occur  over  four 
times  this  volume ;  and  at  intervals  of  a  few  thousand  years  a  flood 
may  be  expected  surpassing  five  times  the  volume  that  is  exceeded  on 
an  average  but  once  a  year.  It  thus  appears  that  the  largest  possible 
flood  may  not  have  occurred  on  any  California  stream  since  white  man 
has  resided  here,  and  that  the  greatest  flood  yet  observed  on  any  of  the 
streams  may  be  exceeded  at  any  time,  but  only  at  average  intervals  that 
increase  in  length  as  the  magnitude  of  the  excess  is  greater. 

The  relation  of  the  size  of  floods  to  the  average  interval  of  time 
between  their  occurrence  disclosed  by  the  stream  flow  records  on  four 
typical  streams,  the  Sacramento,  the  Mokelumne,  the  San  Joaquin  and 
the  San  Gabriel  rivers,  is  set  forth  on  Plate  II,  "Probable  Frequency 
of  Flood  Discharge."  For  convenience  of  comparison,  the  rate  of 
flood  run-off  is  here  expressed  as  inches  depth  of  run-off  in  twenty-four 
hours  on  the  tributary  drainage  area.  A  multiplying  factor  is  given 
on  each  chart  to  convert  the  values  of  depth  of  run-off  on  the  drainage 
area  into  mean  rate  of  run-off  for  twenty-four  hours  in  second-feet. 
The  horizontal  scale  expresses  the  frequency  with  which  values  are 
exceeded  in  100  years.  The  dots  plotted  on  the  charts  are  the  floods  on 
the  respective  streams  taken  from  the  records  of  measured  stream  flow 
that  have  been  maintained  for  the  past  twenty  to  thirty  years.  The 
actual  occurrences  counted  from  the  records  have  been  expanded  by 
iiroportion  to  obtain  the  probable  number  that  would  have  occurred  had 
the  record  been  100  years  in  length.  Double  logarithmic  scales  were 
used  in  plotting  these  charts  because  of  the  convenience  in  shape  of  the 
resulting  curves. 

To  illustrate  the  interjiretation  of  Plate  II,  reference  is  made  to  the 
upper  diagram  portraying  the  probable  frequency  of  flood  occurrence 
on  the  Sacramento  River  near  Red  Bluff.  On  this  diagram  the  hori- 
zontal scale  represents  frequency.  The  whole  figure  1  represents  one 
flood  crest  in  100  years.  One-tenth  represents  one-tenth  of  a  flood  in 
100  years  or  one  flood  in  1000  years.  Similarly  4  represents  fonr 
flood  crests  in  100  years  or  one  each  25  years.  Following  up  the  verti- 
cal line  labeled  4  on  the  horizontal  frequency  scale,  to  intersection  with 
the  curve,  it  will  be  noted  that  the  A-alue  opposite  the  intersection  on 
the  vertical  scale  of  run-off  on  the  left  is  one.  This  means  that,  on  an 
average,  four  flood  crests  in  100  years,  or  one  in  twenty-five  years,  will 
probably  exceed  one  inch  in  depth  of  run-off  in  twenty-four  hours  on 
the  tributary  drainage  area.  This  rate  of  flood  run-off  is  converted  into 
second-feet  by  multiplying  by  the  factor  248,937  (shown  on  the  face 
of  the  diagram).     Thus  249,000  second-feet  mean  dailv  flow  mav  be 


*  Chap.  V.  Bui.  No.  .'>,  "Flow  in  California  Streams,"  of  the  Division  of  Engineering 
and  Irrigation,  State  Department  of  Public  Works. 


24 


WATER   RESOURCES   OF    CALIFORNIA. 


exceeded  on  an  average  of  once  in  25  years.  For  convenience,  this 
value  has  been  referred  to  in  Chapter  I  as  the  "once-in-25-year  flood." 
It  approximates  the  flood  called  "maximum"  in  the  usual  engineering 
parlance  of  this  locality. 

It  may  be  observed  on  Plate  II  that  tlie  plotted  data  fairly  define 
curves  of  regular  shape  that  may  be  extended  beyond  the  limits  of  the 
observations.  By  so  doing,  some  comprehension  may  be  gained  of  the 
frequency  with  Avhicli  floods  might  occur  greater  tlian  those  a})pearing 
in  the  comparatively  short  period  of  observation.  The  following  table, 
obtained  by  scaling  the  charts,  sliows  how  rarely  the  excessively  large 
floods  occur.  It  also  sIioavs  how  the  size  of  flood,  that  may  be  expected 
at  increasing  intervals,  grows  larger  quite  rapidlj^  up  to  those  occurring 
on  an  average  of  once  in  twenty-five  years.  For  longer  intervals  the 
size  groAvs  larger  less  rapidly. 

DEPTH  OF  FLOOD  RUN-OFF  ON  DRAINAGE  AREA  OF  FOUR 
ILLUSTRATIVE  STREAMS  IN  INCHES  PER  24  HOURS. 


Frequency  with  which  values  are  exceeded 

River 

Ouce 
a  year 

Once  in 
10  years 

Once  in 
25  years 

Once  in 
50  years 

Once  in 
100  years 

Once  in 
1000  ynars 

0.44 
0.51 
0.40 
0.49 

0.85 
0.89 
0.71 
2.49 

1.00 
1.05 
0.81 
3.34 

1.15 
1.15 
0.89 
4.00 

1.25 
1.25 
0.96 
4.62 

1.65 

Mokclumne*  

1.61 

San  Joaquin 

1.22 

6.74 

It  is  seen  that  the  depth  of  flood  run-off  from  the  drainage  areas  of 
tlie  three  streams  north  of  Teliacha])i  Pass  is  much  alike  for  large 
floods,  except  that  it  is  slightly  smaller  on  the  San  Joaquin  River. 
The  depth  of  flood  run-off  on  the  San  Gabriel,  a  typical  stream  of 
southern  California,  is  several  times  as  great  for  large  floods  as  on  the 
northern  streams.  It  shows  how  much  larger  floods  in  pro]iortion  to 
the  size  of  their  drainage  areas  dcvelo])  on  the  southern  streams. 

The  foregoing  table  of  frequency  of  flood  flows  on  the  four  illustra- 
tive streams,  in  expressing  the  rate  of  run-off  in  inches  depth  on  the 
drainage  area  per  twenty-four  hours,  does  not  show  the  actual  magni- 
tude of  the  flood  values.  The  following  table  expresses  the  values 
parallel  to  the  former  table  in  second-feet.  These  are  the  estimated 
quantities  at  the  gaging  station  on  each  stream  near  the  edge  of  the 
valley  floor. 

♦Water  Supply  Paper  No.  551  of  the  United  States  Geological  Survey,  recently 
published,  places  the  maximum  discharge  of  the  Mokelumne  River  at  Clements  at 
25,500  second  feet.  This  is  obtained  bv  applying  the  rating  curve  of  the  1911  flood 
to  the  gage  heights  of  1907.  The  crest  discharge  of  the  1907  flood  has  been  pub- 
lished as  17,000  second  feet  in  former  publications  including  Water  Supply  Paper 
No.  299  in  which  are  printed  the  daily  discharges  of  the  1907  flood.  The  figures 
contained  in  Water  Supply  Paper  No.  299  have  been  used  in  preparing  this  volume. 
Should  the  daily  discbarges  of  the  1907  flood  be  revised  by  application  of  the  1907 
gage  heights  to  the  1911  rating  curve,  the  increase  in  their  values  would  be  so  sub- 
stantial as  to  require  a  complete  revision  of  the  analyses  of  floods  on  the  Mokelumne 
Hiver  contained  in  this  volume  in  ordei-  to  make  the  analyses  harmonize  with  the 
increased  discharge  values. 


THE    CONTROL   OF   FLOODS   BY    RESERVOIRS. 


25 


FLOOD  RUN-OFF  OF  THE  FOUR  ILLUSTRATIVE  STREAMS  IN 
SECOND-FEET. 


Frequency  with  which  values  are  exceeded 

River 

Once 
a  year 

Once  in 
10  years 

Once  in 
25  years 

Once  in 
50  years 

Once  in 
100  years 

Once  in 
1000  years 

109,000 
8,700 
17,500 
2,800 

212,000 
15,100 
31.200 
14,300 

249,000 
17,800 
35,600 
19,200 

286,000 
19,500 
39,000 
23,000 

311,000 
21,200 
42,100 
26,600 

411,000 

27  400 

53,500 

38  800 

It  is  interesting  to  note  in  examining  tlie  charts  of  Plate  II  that, 
even  with  the  continued  extension  of  these  curves  to  intervals  of  time 
thousands  of  j-ears  long,  the  size  of  floods  still  grows  larger  with  the 
increasing  length  of  the  interval.  This  indicates  that  there  probably 
is  no  limit  to  the  size  of  floods  that  may  occur,  but  that  the  very  largest 
ones  occur  only  at  intervals  of  many  thousands  of  years.  It  would 
appear,  therefore,  that  absolute  protection  from  floods  is  impossible  and 
that  the  degree  of  protection  desired  should  be  carefully  considered 
in  laying  out  protective  systems. 

Because  of  the  unlimited  size  in  wliich  floods  may  occur,  flood  control 
embodies  an  economic  ([uestion  as  to  the  size  for  which  protective  works 
should  be  designed.  The  engineering  i)rofession  has  generally  accepted 
designs  based  upon  the  greatest  flood  of  record  or  upon  a  more  or  less 
arbitrary  increase  to  it  resulting  from  a  study  of  high  water  marks  or 
the  memory  of  old  inhabitants.  The  foregoing  analysis,  however,  shows 
that  all  of  these  may  be  exceeded  at  long  intervals  of  time.  The  design 
floods  used  in  the  adopted  flood  control  plan  **  for  the  Sacramento 
Valley,  the  greatest  work  in  flood  control  consummated  in  California, 
are  found  to  closely  approximate  the  mean  dail}^  values  that  may  be 
exceeded  on  an  average  of  once  in  twenty-five  years.  The  design 
quantities  adopted  by  the  California  Debris  Commission  in  1911  were 
revised  in  1925  after  further  study.  Both  the  original  and  revised 
quantities  are  compared  to  the  once-in-25-year  values  in  the  following 
table : 


*  Water  Supply  Paper  No.  551  of  the  United  States  Geological  Survey,  recently- 
published,  places  the  maximum  discliarge  of  tlie  Mokelumne  River  at  Clements  at 
25,500  second  feet.  This  is  obtained  by  applying  the  rating  curve  of  the  1911  flood 
to  the  gage  heights  of  1907.  The  crest  discharge  of  the  1907  flood  has  been  pub- 
lished as  17,000  second  feet  in  former  publications  including  Water  Supply  Paper 
No.  299  in  which  are  printed  the  ctaily  discharges  of  the  1907  flood.  The  figures 
contained  in  Water  Supply  Paper  No.  299  have  been  used  in  preparing  tliis  volume. 
Should  the  daily  discharges  of  the  1907  flood  be  revised  by  application  of  the  1907 
gage  heights  to  the  1911  rating  curve,  the  increase  in  their  values  would  be  so  sub- 
.stantial  as  to  require  a  complete  revision  of  the  analyses  of  floods  on  the  Mokelumne 
River  contained  in  this  volume  in  order  to  make  the  analyses  harmonize  with  the 
Increased  discharge  values. 

**  Report  of  California  Debris  Commission,  .Tune  29,  1911, 


26 


WATER   RESOURCES   OF    CALIFORNIA. 


COMPARISON  OF  DESIGN  FLOOD  FLOW  USED  BY  CALIFORNIA  DEBRIS 
CONLMISSION  IN  SACRAMENTO  VALLEY  FLOOD  CONTROL  PROJECT 
WITH  THE  ONCE-IN-25-YEAR  VALL'ES  OF  THE  WATER  RESOURCES 
INVESTIGATION. 


Stream 


Design  flood  flows  of 

California  Debris  Commission 

in  second-feet 


1911  Report 


1925  Report 


I  Flood  flows  (av.  24  hrs.) 
exceeded  once  in  25  years 
i       Water  Resources 
■j  Investigation 

I         in  second-feet 


Sacramento  River  near  Red  Bluff 250.000 

Feather  River 150.000 

Yuba  Ri%er ;  110,000 

Bear  River 30,000 

American  River 120,000 

Stony  Creek 1  30.000 

Cache  Creek 20.000 

Putah  Creek 25.000 


260.000 
180,000 
120.000 
30.000 
128.000 
30.000 
20.000 
25.000 


249,000 
171.000 
128.000 
29.000 
119.000 
45.000 
20.000 
46.000 


In  the  Sacramento  Valley  the  crest  discharge  of  large  floods  is 
approximately  10  per  cent  greater  than  the  average  flow  for  twenty- 
four  lioiirs.  Therefore,  the  crest  of  the  once-in-25-year  flood  would 
encroach  upon  the  freeboard  of  the  levees  of  the  Debris  Commission 
plan  to  the  extent  of  about  10  i)er  Cf^iit  of  the  channel  capacity.  Since 
this  encroachment  on  the  freeboard  would  be  of  only  a  few  liours' 
duration,  with  usual  maintenance,  tiie  works  as  planned  should  protect 
the  project  against  floods  that  will  not  be  exceeded  on  an  average 
oftener  than  once  in  twenty-five  years.  Because  of  the  difficulty  in 
parts  of  the  project,  not  intensively  cultivated,  of  meeting  asse.s.sments 
for  the  work  from  the  sale  of  products  of  the  land,  it  is  believed  that 
this  ]U'otection  is  greater  than  these  lands  can  now  afford.  On  the 
other  hand,  perhaps  it  is  not  a  sufficient  degree  of  protection  for  the 
intensively  cultivated  sections  and  the  thickly  populated  areas  about 
the  City  of  Sacramento.  It  would  seem  that  at  least  the  design  flood 
for  the  American  River,  which  directly  menaces  the  City  of  Sacra- 
mento, should  be  relatively  larger  than  for  other  parts  of  the  project. 
Thus,  the  degree  of  protection  employed  in  designing  flood  control 
projects  should  be  governed  by  the  class  of  territory  to  be  protected. 
Logically,  it  should  be  increased  from  time  to  time  as  the  territory 
becomes  more  thickly  populated  and  property  values  become  larger. 
The  analysis  here  presented  offers  a  convenient  means  of  expressing 
the  degree  of  ])rotection  of  any  project  in  terms  of  the  average  interval 
of  time  in  wliidi  the  design  flood  may  be  expected  to  be  exceeded. 


THE    CONTROL    OF   FLOODS   BY   RESERVOIRS.  27 

CHAPTER  III. 


THE  PRINCIPAL  CHARACTERISTICS  OF  FLOOD 
OCCURRENCE. 


Regularity   of  flood    occurrence. 

It  has  been  pointed  out  in  Chapter  II,  that  the  records  of  stream  flow 
in  California  disclose  a  relation  between  the  size  of  floods  and  the 
average  frequency  of  their  occurrence.  Floods  occur  in  their  varying 
sizes  at  regular  average  intervals  throughout  long  periods  of  time. 
Although  floods  happen  almost  every  year,  only  the  smaller  ones  are  at 
all  frequent.  Extremely  large  floods  occur  at  such  long  average  inter- 
vals that  several  generations  may  pass  without  witnessing  one  of  greatest 
magnitude.  This  relation  disregards  the  sequence  with  which  the 
various  sizes  follow  one  another  and  expresses  only  the  average  frequency 
of  their  occurrence.  A  glance  at  the  records  is  conclusive  that  the  actual 
sequence  is  most  irregular  although  the  average  occurrence  seems  to 
follow  a  regular  behavior. 

The  combination  of  this  irregularity  in  sequence  of  the  various  size 
floods  and  the  long  average  intervals  between  the  large  ones,  creates  an 
impression  of  erratic  behavior  in  flood  occurrence  that  is  not  indicated 
by  a  close  analysis  of  the  records.  A  study  of  the  records  shows  that  a 
degree  of  systematic  behavior  exists  sufficient  to  determine  within  useful 
limits  certain  characteristics  as  to  the  time  of  year  and  the  amount  of 
previous  precipitation  in  the  season  with  which  they  occur.  However, 
this  behavior  is  not  so  systematic  that  the  relations  may  be  discussed  by 
directly  plotting  the  quantities  on  coordinate  paper  in  the  usual  manner ; 
rather  they  must  be  approached  by  determining  limiting  values  within 
which  all  events  occur.  The  limiting  values  to  these  relations  found  to 
characterize  floods  by  these  investigations,  are  presented  herewith.  They 
concern  the  time  of  year,  the  previous  seasonal  rainfall,  and  the  seasonal 
run-off  subsequent  to  flood  occurrence. 

Time   of  year  of  flood    occurrence. 

The  sharp  division  of  the  California  year  into  a  wet  and  dry  season 
is  of  common  knowledge.*  Precipitation  in  any  quantity  is  confined  to 
the  six  months  period  from  November  1st  to  May  1st  while  the 
remaining  six  months  are  for  the  most  part  warm  and  dry.  Except  in 
the  desert  sections  of  the  State  and  on  streams  fed  by  extensive  snow 
fields,  floods  occur  only  during  the  rainy  season ;  however,  the  extent  to 
which  the  flood  season  varies  through  the  six  months  in  which  rains 
occur,  is  not  generally  appreciated.  Stream  flow  records  indicate  that 
the  time  of  year  in  which  the  largest  floods  occur  is  limited  to  mid- 
winter and,  during  the  remainder  of  the  six  months  period  of  rain, 
only  lesser  floods  occur  in  sizes  that  become  smaller  toward  either 
extremity  of  the  season  until  a  date  is  disclosed  before  and  after  which 
floods  do  not  occur.    On  streams  fed  by  extensive  snow  fields,  floods  of 

•  For  full  exposition  see  Chap.  II,  Bui.  No.  6,  "Irrigation  Requirements  of  Cali- 
fornia Lands,"  of  Division  of  Engineering  and  Irrigation.  State  Department  of  Public 
Works. 


28 


WATER   RESOURCES   OF    CALIFORNIA. 


PLATE  III. 


SACRAMENTO   RIVER    NEAR  RED  BLUFF 

1895-19  25 

SEPT.   i    OCT. 

NOV. 

DEC. 

JAN     *>FEB.    i    MAR.  ■  APRIL  \    MAY 

JUNE       JULY    1    AUG.    j 

FebZ.iaS     Veb.3.1909 

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MOKELUMNE    RIVER    NEAR  CLEMENTS 
1904-1925 

c 
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SEPT.      OCT. 

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SAN  GABRIEL  RIVER  NEAR  AZUSA 
1895-1925 

SEPT. 

OCT. 

NOV. 

DEC. 

JAN.    j    FEB. 

MAR. 

APRIL 

MAY 

JUNE 

JULY 

AUG. 

\Jan.l8,l9l6 

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i 

Plot  of  All  Floods  of  Record-Years  Superimposed 

THE    CONTROL    OF   FLOODS   BY    RESERVOIRS.  29 

medium  size  occur  in  the  early  summer  after  the  close  of  the  precipi- 
tation season.  These  floods,  fed  bj^  melting  snow,  are  not  as  large  but  are 
of  longer  duration  than  those  fed  from  rainfall.  They  have  their  special 
characteristics.  An  extended  investigation  of  the  time  of  year  of  flood 
occurrence  was  made  on  streams  having  the  longest  record  of  measure- 
ments. In  order  to  avoid  a  tiresome  review  of  similar  data,  those  of  four 
typical  streams  only  are  presented,  the  Sacramento,  Mokelumne,  San 
Joaquin  and  San  Gabriel  rivers.  These  data  are  displayed  on  Plate  III, 
' '  Plot  of  All  Floods  of  Record — Years  Superimposed. ' '  A  dot  is  plotted 
on  this  plate  for  every  flood  of  record  both  large  and  small,  at  the  day 
of  its  occurrence  indicated  on  the  horizontal  time  scale.  The  size  of 
each  flood  in  second-feet  is  shown  on  the  vertical  scale. 

The  great  preponderance  of  small  floods  and  the  apparent  irregu- 
larity in  occurrence  of  the  larger  ones  may  be  observed  at  once  by  the 
relative  position  of  the  dots.  The  manner  of  their  clustering  also 
illustrates  how  the  larger  floods  occur  during  the  midwinter  months  and 
how  their  magnitude  decreases  towards  the  fore  and  latter  part  of  the 
season. 

The  dots  of  greatest  height  on  the  graphs  are  in  the  midwinter 
months  for  all  four  streams.  These  represent  rain-water  floods.  The 
dots  on  the  plots  for  the  Mokelumne  and  San  Joaquin  rivers  forming 
a  distinct  cluster  in  the  early  summer  months,  but  of  lesser  height, 
represent  floods  resulting  from  rapidly  melting  snow  on  the  high 
mountainous  parts  of  their  drainage  areas.  The  Sacramento  and  San 
Gabriel  drainage  areas  do  not  have  sufficient  precipitation  as  snow  to 
cause  floods  during  the  melting  season.  Most  of  the  snow  that  falls  on 
these  drainage  areas  melts  in  the  early  spring  and  augments  the  run-off 
from  rainfall.  It  is  interesting  to  note  from  the  manner  in  which  the 
two  groups  of  dots  cluster,  that  floods  from  melting  snow  occur  with 
greater  frequency  and  regularity  than  those  from  rainfall  but,  in 
general,  do  not  attain  much  more  than  half  the  size  of  the  large  mid- 
winter rain-water  floods. 

The  position  of  the  dots,  in  relation  to  the  time  scale  of  the  diagram, 
indicates  dates  before  and  after  which  floods  of  much  size  have  not 
occurred  within  the  20  to  30  years  of  record  on  these  streams.  These 
dates  vary  somewhat  on  the  several  streams  but,  in  general,  floods 
resulting  from  rainfall  occur  between  November  1st  and  May  1st  with 
the  largest  ones  in  the  months  of  January,  February  and  March.  The 
snow-water  floods  occur  between  May  1st  and  August  1st  with  the 
greatest  ones  in  the  first  half  of  June. 

Limiting   dates   to  the   flood   season. 

While  Plate  III,  "Plot  of  All  Floods  of  Record— Years  Superim- 
posed," furnishes  a  perspective  of  the  time  of  year  during  which  floods 
of  the  various  sizes  occur,  a  closer  analysis  is  desirable  for  working 
purposes.  It  may  be  observed  on  Plate  III  that  the  relation  betAveen  the 
size  of  floods  and  the  time  of  their  occurrence  is  rather  broad  in  its 
character.  There  appears,  however,  to  be  certain  limiting  dates  for  the 
medium  and  large  floods  before  and  after  which  the  many  records  of 
daily  run-off  disclose  neither  an  instance  of  nor  a  tendency  toward  floods 
of  that  size  occurring.  For  a  close  valuation  of  these  limiting  dates,  it 
is  not  enough  to  enter  the  records  of  occurrence  and  select  the  dates 


30 


WA'lKli    RESOURCES    OK    (AI.II'OkXIA. 


PLATE    IV. 


SACRAMENTO 

RIVER 

NEAR 

RED  BLUFF 

1 II 

S^bol 

Size  0*"  flow  cjtceedcd 
*^'^'^S««^fee. 

Aufi. 

I 

30            74.700 
40            99.fr00 
50          I24,5(J0 
60          149.400 
70       1    174.300 

,llllV 

June 

i 



Mav 

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j  1 1 1 

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placed  at  the  side  of  A 

Oct 

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cates  the 

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sept 

100 


1.000 


10,000 


SAN 

GABRIEL  RIVER 

NEAR 

AZUSA 

' 

,S-:-orf'o..e.c^ede«| 

Au^. 

Symbol 

»?e°a''r'Ui^«<'"d'«' 

: 

10               1,900 
20              3,800 
30              5,800 
40              7.700 

JlllV 

r     1       50       1       9.600  1 
«            60       1      11.500 
•     1       70       1      13,400  1 

.June 

_.„.,.. 

^TT 

r~r 

Mav 

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Mar, 

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t 

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Feb 

UmltM.dalss 

between 
excess 

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f^ 

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Imifiiitinljks  of 
ectancyoffbwsin 
ESS  of  specified  Size 



whicntTows  ir 

1  ^i^n^j^'^^.T*   7" 

r  **' 

of  specified  size  occur. 

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10,000 


Number  of  daj/s  in  100  ^ears  on  which  flows  are  exceeded 


Relation  of  Time  of  Year  to  Flood  Occurrence 


CURVES  SHOW  NUMBER  OF  DAYS  IN  100  YEARS  ON 
WHICH  FLOWS  OCCUR  IN  EXCESS  OF  SPECIFIED  SIZE 
PRIOR      AND     SUBSEQUENT      TO     INDICATED      DATES 

Flows  expressed  in  per  cent  of  greatest  dail^  rate  of  flow  of  once-in-25->ear  flood 


THE    CONTROL    OF    FLOODS    BY    RESERVOIRS.  31 

before  and  after  which  largo  floods  have  not  occurred.  In  so  doing,  no 
conception  would  be  gained  of  the  reliance  that  could  be  placed  upon 
their  future  occurrence  within  the  dates  selected. 

In  order  to  determine  as  well  as  may  be,  the  reliance  that  may  be 
placed  on  selected  limiting  dates,  the  daily  stream  flow  records  of  twenty 
streams  were  analyzed  in  regard  to  the  frequency  with  which  specified 
flows  were  exceeded  both  prior  and  subsequent  to  various  dates  during 
the  season.  The  analysis  tabulated  the  occurrences  within  the  period 
of  record  so  that  their  frequencj^  could  be  counted.  The  frequencies 
counted  from  the  records  of  the  four  illusti*ative  streams,  are  plotted  on 
Plates  IV  and  V,  "Relation  of  Time  of  Year  to  Flood  Occurrence." 
Plate  IV  presents  the  data  for  the  Sacramento  and  San  Gabriel  rivers 
and  Plate  V  for  the  Llokelumne  and  San  Joaquin  rivers.  The  rates  of 
flow  are  expressed  in  relation  to  that  of  a  once-in-25-year  flood  for  con- 
venience of  comparison  between  streams.  A  conversion  table  to  second 
feet  is  given  on  each  diagram.  Cross-section  paper  ruled  to  logarithmic 
scale  in  one  direction  was  used,  since  it  was  found  by  trial  that  more 
satisfactory  graphs  could  be  obtained  by  so  doing. 

Smooth  curves  were  drawn  approximating  the  trend  of  these  data  and 
labeled  with  the  rate  of  flow  for  which  the  computations  were  made. 
There  are  two  curves  in  each  diagram  for  the  same  rate  of  flow,  one  full- 
line  and  one  dotted-line  curve.  The  full-line  curve  show^s  the  probable 
frequency  with  which  the  specified  flow  is  exceeded  prior  to  the  date 
indicated  on  the  vertical  scale.  The  dotted-line  curve  shows  the  probable 
frequency  with  which  it  is  exceeded  subsequent  to  the  date  indicated  on 
the  vertical  scale.  While  it  is  evident  that  the  data  do  not  disclose  exact 
relationships,  it  may  be  noted  that  the  curves  representing  the  smaller 
flows  are  fairly  well  defined.  More  data  are  available  concerning  small 
flows  than  large  ones  for  they  appear  a  greater  number  of  times  in 
the  records.  The  short  term  of  the  records  relative  to  the  infrequent 
occurrence  of  large  flood  flows  prevents  their  containing  adequate  data 
for  displaying  the  relations  plainly.  Were  there  as  many  data  con- 
tained in  the  comparatively  short  records  concerning  the  larger  flows 
as  there  are  for  the  smaller  ones,  it  seems  probable  that  their  curves 
would  be  equally  well  defined.  However,  the  curves  for  the  larger 
values  take  logical  positions  in  relation  to  available  data  when  drafted 
by  comparison  with  the  data  for  the  smaller  flows. 

The  advantage  of  the  analysis  delineated  on  Plates  IV  and  V  is  that 
the  curves  of  relationship  developed  from  the  data  collected  during  a 
quarter  century,  may  be  extended  to  indicate  expectancies,  had  the 
records  covered  much  longer  periods  of  time.  For  instance,  by  extend- 
ing these  curves  to  intersect  the  0.1  line  on  the  frequency  scale,  the 
time  of  the  year  before  and  after  Avhich  greater  flows  than  the  specified 
sizes  do  not  occur  oftener  than  one  day  in  a  thousand  years  (0.1  day  in 
100  years)  is  indicated  on  the  vertical  time  scale  by  the  points  of  inter- 
section. Intercepts  of  the  full  and  dotted-line  curves  on  other  verticals 
than  the  0.1  line,  indicate  on  the  vertical  time  scale,  the  period  of  the 
3^ear  before  and  after  which  the  specified  flows  are  exceeded  more  fre- 
quently than  one  day  in  a  thousand  years.  The  frequency  with  which 
they  are  exceeded  is  .shown  by  the  position  of  the  vertical  line  inter- 
sected by  the  two  curves  on  the  horizontal  frequency  scale. 


32 


WATER    KESOURCES   OF   CALIFORNIA. 


PLATE  V. 


MOKELUMNE  RIVER  NEAR  CLEMENTS 


1,000 

SAN  JOAQUIN  RIVER  NEAR  FRIANT 


10,000 


10  100  1,000  10,000 

Number  of  days  in  100  years  on  which  flows  are  exceeded 


Relation  of  Time  of  Year  to  Flood  Occurrence 


CURVES  SHOW  NUMBER  OF  DAYS  IN  100  YEARS  ON 
WHICH  FLOWS  OCCUR  IN  EXCESS  OF  SPECIFIED  SIZE 
PRIOR      AND     SUBSEQUENT     TO     INDICATED     DATES. 


Flows  expressed  in  per  cent  of  greatest  dail^  rate  of  flow  of  a  once-in-25-^ear  flood. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS.  33 

By  way  of  illustration  of  the  interpretation  of  these  plates,  reference 
is  made  to  the  upper  chart  on  Plate  IV,  showing  the  relation  of  the  time 
of  year  to  flood  occurrence  on  the  Sacramento  River  near  Red  Bluff. 
Selecting  the  vertical  ordinate  that  passes  through  the  figure  1  on  the 
horizontal  frequency  scale,  it  is  seen  to  intersect  the  full-line  curve 
labeled  50  per  cent,  opposite  November  22d  on  the  vertical  time  scale 
to  the  left.  This  means  that  on  an  average  of  one  day  in  100  years  there 
probably  will  be  a  flow  exceeding  50  per  cent  of  a  once-in-25-year  flood 
prior  to  November  22d.  Following  the  same  vertical  ordinate  to  inter- 
section with  the  dotted-line  curve  labeled  50  per  cent,  it  is  seen  that  the 
intersection  is  opposite  April  12th  on  the  time  scale  to  the  left.  This 
means  that  on  an  average  of  one  day  in  100  years,  a  flow  exceeding  50 
per  cent  of  a  once-in-25-year  flood  will  probably  occur  subsequent  to 
April  12th.  Thus,  November  22d  and  April  12tli  are  the  limiting  dates 
of  the  season  for  floods  greater  than  half  the  size  of  the  once-in-25-year 
value  with  the  probability  that  either  limit  may  not  be  exceeded  oftener 
on  an  average  than  one  day  in  100  years. 

The  information  taken  from  Plates  IV  and  V  is  expressed  in  the 
following  tables.  Here  are  given  in  the  several  columns  the  probable 
dates  before  and  after  which  greater  flows  than  the  several  specified 
sizes  do  not  occur  oftener  on  the  average  than  one  day  in  a  thousand, 
one  day  in  a  hundred,  one  day  in  fifty,  one  da.y  in  twenty-five  and  one 
day  in  ten  years.  It  is  interesting  to  observe  in  reviewing  these  tables, 
that,  of  the  365  days  in  the  year,  the  season  for  the  occurrence  of  rain- 
water floods  of  corresponding  size  (equal  per  cent  of  once-in-25-year 
flood)  opens  and  closes  on  the  four  illustrative  streams  with  the  greatest 
variance  in  dates  of  47  days.  It  opens  from  40  to  72  days  earlier  for  the 
smaller  floods  than  for  the  large  ones  and  closes  from  20  to  57  days 
later.  For  decreasing  the  probability  from  one  day  in  10  years  to  one 
day  in  1000  years  that  flows  in  excess  of  those  specified  will  not  occur 
either  before  or  after  these  opening  and  closing  dates,  the  season  opens 
as  much  as  65  days  earlier  and  closes  as  much  as  49  days  later. 

The  season  for  the  occurrence  of  floods  from  rapidly  melting  snow  is 
seen  to  be  less  variable  than  that  for  rain-water  floods.  Of  the  two  illus- 
trative streams  having  snow-water  floods,  the  .season  for  floods  of  corre- 
sponding size  opens  and  closes  within  14  days  of  the  same  dates  and 
these  dates  do  not  change  more  than  23  days  for  decreasing  the  prob- 
ability from  one  day  in  10  years  to  one  day  in  1000  years  that  flows  in 
excess  of  those  specified  will  not  occur  either  before  or  after  the  open- 
ing or  closing  dates. 


3—52411 


34 


WATER   RESOURCES   OF    CALIFORNIA. 


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THE    CONTROL    OP   FLOODS   BY   RESERVOIRS. 


35 


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36 


WATER   RESOURCES   OP    CALIFORNIA. 


Date  of  greatest  flood  expectancy. 

Since  the  analysis  of  flood  occurrence  as  disclosed  by  the  records  of 
the  last  quarter  century  shows  definite  limiting  dates  to  the  flood  season 
before  and  after  which  the  probability  of  their  occurrence  is  exceedingly 
remote,  it  is  reasonable  that  the  flood  expectancy  should  increase 
toward  some  culminating  date  and  then  decrease  as  the  end  of  the 
season  is  approached.  The  data  i)lotted  on  Plate  III,  "Plot  of  All 
Floods  of  Record — Years  Superimposed,"  indicate  such  culminating 
dates  for  the  several  streams. 

On  Plates  IV  and  V,  "Relation  of  the  Time  of  Year  to  Flood  Occur- 
rence," pairs  of  curves  are  drafted,  one  dotted  and  one  full-line,  each 
pair  representing  a  flow  of  a  specified  size.  The  dotted  curves  show 
the  probable  frequency  with  wliich  flows  greater  than  specified  occur 
subsequent  to  the  dates  indicated  on  the  vertical  time  scale.  The  full- 
line  curves  show^  in  a  similar  way,  the  probable  frequency  of  greater 
flows  prior  to  the  date  indicated  on  the  time  scale.  As  the  two  curves 
of  a  pair,  one  dotted  and  one  full-line,  approach  each  other,  flows 
greater  than  the  specified  size  occur  more  frequently  until  the  central 
day  of  the  flood  season  is  reached  at  their  intersection.  On  this  day, 
flows  greater  than  the  specified  size  occur  both  before  and  after  with 
equal  frequency.  It  is  the  central  day  of  oceurrence  for  flows  greater 
than  the  specified  size. 

The  dates  of  the  intersection  of  tlie  several  pairs  of  curves  on  each 
stream  are  nearly  the  same.  On  the  San  Gabriel  they  are  within  one 
day  of  being  the  same,  on  the  Sacramento  three  days,  on  the  San 
Joaquin  seven  days,  and  on  the  INIokelumne  nine  days.  These  dates  are 
so  nearly  alike  for  the  several  size  flows  on  each  stream  that  they  may 
be  taken  as  tlie  culminating  dates  of  flood  expectancy.  They  vary  on 
the  four  illustrative  .streams  from  January  20  to  February  26  for  rain- 
water floods  and,  on  the  two  illustrative  stream.s  having  snow-water 
floods,  from  May  31  to  June  8.  Tliese  dates  are  listed  in  the  following 
table : 


CULMINATING  DATES  OF  FLOOD  EXPECTANCY. 


Size  of  flood 

Date 

In  per  cent  of 
gre.itcst  dfiilv  rate 

Sacramento 
River 

Mokelumne  River 

San  Joaquin  River 

of  (low  of 

once-in-25-year 

flood 

Rain-water 
floods 

Snow-water 
floods 

Rain-water 
floods 

Snow-water 
floods 

San  Gabriel 
River 

10 

Feb.  11 

20 

Feb.  11 

30 
40 
50 

Feb.    8 
Feb.    7 
Feb.    8 
Feb.  10 
Feb.    7 

Feb.  26 
Feb.  23 
Feb.  21 
Feb.  18 
Feb.  17 

May  31 

June    7 

Jan.  27 
Jan.  24 
Jan.  21 
Jan.  20 
Jan.  20 

June    6 
June    7 
June    8 
June    8 

Feb.  10 
Feb.  10 
Feb.  10 

60 

Feb.  10 

76 

Feb.  la 

Preparatory   precipitation  for  flood   occurrence. 

While  Ihc  records  of  stream  flow  show  that  there  is  a  definite  season 
within  whieh  floods  occur  and  that  the  expectancy  of  floods  within 
tliis  season  increases  toward  culmination  at  some  mid-season  dale, 
nevertheless,  the  expectancy  on  the  .successive  days  of  each  season  is  not 


THE   CONTROL    OF   FLOODS   BY   RESERVOIRS.  37 

identical  in  every  year.  Floods  can  not  occur  without  preparatory 
precipitation  to  wet  the  earth's  surface.  If  dry,  this  surface  is  so 
absorbent  that  even  the  heaviest  rains  are  insufficient  to  produce  large 
run-off.  With  the  drainage  area  already  saturated  from  previous  pre- 
cipitation, the  same  high  intensities  produce  run-off  that  concentrates 
in  the  stream  channels  to  form  excessive  floods.  Sometimes,  snow  from 
previous  storms,  melting  in  contact  with  warm  rains,  augments  the 
run-off  from  the  later  storm.  For  these  reasons,  the  precipitation  that 
has  taken  place  prior  to  any  date  in  a  season  markedly  influences  the 
expectancy  of  floods,  and,  since  each  season  has  its  own  peculiar  num- 
ber, intensity  and  sequence  of  storms,  the  flood  expectancy  varies  on 
like  dates  of  different  seasons. 

Tliese  investigations  ha.ve  searched  for  an  index  of  the  degree  of 
preparedness  of  drainage  areas  necessary  for  turning  off  large  floods. 
Since  the  varying  intervals  between  storms  dry  up  the  ground  surface 
to  a  different  extent,  the  amount  of  precipitation  that  precedes  floods  is 
variable.  An  examination  of  the  records  shows  that  large  floods  have 
occurred  only  with  very  substantial  preparatory  precipitation.  The 
following  table  shows  the  seasonal  precipitation  at  the  stations*  used 
in  conjunction  with  the  analysis  of  run-off  records,  prior  to  the  date 
of  the  largest  floods  on  each  of  the  four  illustrative  streams.  The  rain- 
fall is  expressed  both  in  inches  depth  and  in  per  cent  of  that  of  a 
normal  season  up  to  the  date  of  the  flood.  (Season  commencing  on 
July  1.) 

*  These  are  the  principal  rainfaU  stations  in  the  precipitation  divisions  in  which 
the  drainage  areas  lie.  See  Chap.  11,  Bui.  No.  5,  "Flow  in  California  Streams." 
Here  the  State  was  divided  into  twenty-six  areas,  called  "precipitation  divisions," 
in  each  of  which  the  rainfall  at  the  various  stations  has  approximately  like  charac- 
teristics when  expressed  in  relation  to  its  normal  although  the  actual  rain  in  lnche.=! 
at  the  several  stations  may  be  very  different.  The  rain  in  Inches  at  the  selected 
stations  Is  much  less  than  on  the  drainage  areas  for  they  are  all  at  accessible 
locations  of  low  elevation. 


38 


WATER   RESOURCES   OF    CALIFORNIA. 


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June  18 
June    3 
June  12 
June    6 
May  31 
June    1 
May  18 
June  16 
June  10 
May  24 
July     4 
June  22 
June    2 
June  20 
June    2 
May    7 
June    8 
May    9 
May  13 

Size  of  flood  near 

Clements — greatest 

daily  rate  of  flow 

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THE   CONTROL    OP   FLOODS   BY   RESERVOIRS. 


39 


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40  WATER    RESOURCES   OF    CALIFORNIA. 

The  foregoing  tables  show  that  the  largest  floods  of  record  on  the 
four  illustrative  streams  occurred  with  the  per  cent  of  normal  rainfall 
up  to  the  day  of  the  flood,  varying  from  97  to  156,  and  the  second  larg- 
est floods  from  71  to  155.  Of  the  twenty  largest  floods  of  record,  those 
on  the  Sacramento  occurred  with  rainfall  varying  from  71  to  168  per 
cent  of  normal ;  those  on  the  Mokelumne,  from  76  to  163  per  cent  of 
normal ;  those  on  the  San  Joaquin,  from  77  to  167  per  cent  of  normal ; 
and  those  on  the  San  Gabriel,  from  66  to  263  per  cent  of  normal.  There- 
fore, it  is  seen  that  ])recipitation,  at  least  in  amount  equivalent  to  a 
substantial  part  of  that  for  a  normal  season,  preceded  all  the  large 
floods  of  record  on  the  four  illustrative  streams.  In  71  i)er  cent  of  the 
instances  tabulated  above,  the  seasonal  precipitation  up  to  the  date  of 
the  flood  was  larger  than  that  for  a  normal  season  up  to  the  same  date. 
Although  it  is  evident  from  these  figures  that  the  per  cent  of  normal 
rainfall  up  to  any  date  in  a  season  is  an  extremely  approximate  indica- 
tion of  the  degree  of  preparedness  of  a  drainage  area  for  turning  off 
floods,  nevertheless,  in  conjunction  with  another  element  of  the  analysis, 
it  was  found  to  have  a  practical  value  greater  than  any  other  index  of 
a  simple  nature.  This  other  element  is  the  approach,  in  any  part  of  a 
season,  to  the  limit  of  rain-producing  capacity  of  weather  sequences. 

It  is  a  matter  of  common  observation  that  sunshine,  clouds,  winds 
and  rain  follow  one  another  in  various  complicated  sequences.  The 
state  of  the  weather  on  any  day  is  known  to  be  the  result  of  pre- 
ceding atmospheric  events  over  a  large  territory  combining  with  the 
seasonal  cycles  peculiar  to  each  geographic  location.  IMany  actions  and 
reactions  liave  followed  one  another  in  finally  producing  the  resulting 
weather  on  any  particular  day.  The  intensity  and  duration  of  rain 
storms  are  a  product  of  these  intricate  sequences.  They  are  limited  in 
value  by  the  reactions  to  their  occurrence  which  induce  succeeding 
states  of  weather  other  than  rain. 

An  inspection  of  precipitation  records  is  convincing  that  these 
reactions  are  effective  in  limiting  both  the  intensity  and  duration  of 
storms,  for  the  large  values  appear  in  the  records  only  occasionally, 
less  often  as  they  become  larger.  A  conception  of  the  capacity  of 
weather  sequences  to  produce  precipitation  in  unusual  amounts  may  be 
gained  by  comparing  the  total  season's  precipitation  of  the  largest 
years  with  that  of  a  normal  season.  If  these  sequences  had  unlimited 
capacity  to  produce  precipitation  it  would  show  in  correspondingly 
large  departures  from  normal  in  the  season's  rain.  The  following 
tabulation  of  the  five  seasons  of  greatest  precipitation  at  the  rainfall 
stations  used  in  conjunction  with  tlie  run-off  records  of  the  four  illus- 
trative streams  shows  only  two  instances  of  the  seasonal  preci])itation 
exceeding  twice  tlie  normal.  Therefore,  it  would  seem  reasonable  that 
the  approach  toward  the  limit  of  precipitation  producing  capacity  at 
any  time  during  the  season  might  be  measured  approximately  by  tlio 
degree  of  normalcy  of  the  precipitation  at  that  time.  Thus,  Avhen  the 
precipitation  at  any  time  ai)proaches,  say,  twice  that  of  a  normal  season 
up  to  the  same  date,  it  would  seem  reasonable  that  there  would  be  small 
likelihood  of  additional  heavy  .storms  because  of  the  exceptionally  large 
amount  of  precipitation  that  must  have  already  occurred  to  place  the 
season  so  far  ahead  of  normal.  Such  a  measure  would  necessarily  lack 
accuracy  during  the  first  few  months  of  the  rainy  season  wliile  the  value 
of  normal  precipitation  is  a  small  quantity.    Until  the  season  progresses 


THE    CONTROL    OF   FLOODS   BY    RESERVOIRS. 


41 


sufficiently  for  normal  precipitation  to  date  to  become  a  substantial 
quantity,  it  is  a  poor  base  for  comparison  because  the  relative  value  is 
considerably  affected  by  small  amounts  of  additional  precipitation.  For 
the  greater  part  of  the  season,  however,  normal  precipitation  to  date 
affords  a  convenient  base  with  which  to  compare  the  precipitation  of 
the  current  season. 

FIVE  SEASONS  OF  LARGEST  PRECIPITATION  AT  U.  S.  WEATHER 
BUREAU  STATIONS. 


Red  Bluff,  1877-1921 

Electra,  1904-1921 

Fresno,  1881-1921 

Ciaremont,  1891-1921 

'  Precipitation 
Season       |   in  per  cent 
1     of  normal 

Season 

Precipitation 
in  per  cent 
of  normal 

Season 

Precipitation 
in  per  cent 
of  normal 

Season 

Precipitation 
in  per  cent 
of  normal 

1877-78 
1889-90 
1885-86 
1914-15 
1905-06 

215 
169 
142 
141 
140 

1906-07 
1910-11 
1905-06 
1908-09 
1913-14 

156 
146 
130 
119 
117 

1885-86 
1883-84 
1894-95 
1905-06 
1889-90 

202 
194 
152 
140 
135 

1913-14 
1906-07 
1915-16 
1892-93 
1894-95 

160 
136 
135 
131 

127 

For  convenience,  the  ratio  of  the  actual  precipitation  up  to  any  date 
in  a  season  to  the  normal  amount  up  to  the  same  date  (season  com- 
mencing July  1),  has  been  named  the  "Progressive  Rainfall  Index" 
because  its  value  changes  daily  as  the  season  progresses.  Plate  VI, 
"Progressive  Rainfall  Index  at  Time  of  Flood  Flow,"  displays  the 
values*  of  this  index  at  the  time  of  every  recorded  flood  on  the  four 
illustrative  streams.  Each  dot  on  the  graph  represents  one  flood  and 
shows  its  greatest  24-hour  rate  of  discharge  on  the  vertical  scale  and 
the  value  of  the  ' '  progressive  rainfall  index ' '  on  the  other.  All  floods  of 
record  are  plotted. 

It  may  be  observed  on  this  plate  that,  of  all  the  floods  of  record  on 
these  four  typical  streams,  those  within  the  highest  quarter  on  the  dis- 
charge scale  occurred  with  values  of  the  progressive  rainfall  index 
lying  betw^een  90  and  150 ;  those  within  the  third  quarter  occurred 
with  indices  between  70  and  180;  those  within  the  second  quarter  with 
indices  between  50  and  270 ;  and  those  within  the  lowest  quarter  on  the 
discharge  scale  with  indices  between  values  of  10  and  567.  Thus,  it  is 
seen  that  the  great  floods  do  not  occur  with  either  small  or  large 
values  of  the  progressive  rainfall  index.  On  the  one  hand,  the  small 
index  values  witness  lack  of  preparatory  precipitation,  while,  on  the 
other  hand,  the  large  index  values  witness  that  the  heavy  rains  for  that 
part  of  the  season  have  already  taken  place. 

Limiting  values  of  progressive  rainfall   index  between  which  floods  occur. 

Although  the  progressive  rainfall  index,  by  its  nature,  can  be 
neither  an  accurate  index  of  conditions  on  the  drainage  area  nor  of  the 
temporary  approach  in  any  part  of  the  season  to  the  limit  of  the  rain- 

*  The  values  of  the  Index  for  each  stream  were  computed  from  the  records  at 
the  principal  rainfall  station  in  the  precipitation  division  in  which  the  drainage 
area  lies.  These  precipitation  divisions  are  defined  by  the  analysis  of  precipitation  in 
California  contained  in  Chap.  II  of  Bui.  No.  5,  "Flow  in  California  Streams." 
Here  the  state  was  divided  into  twenty-six  areas,  called  "precipitation  divisions,"  in 
each  of  which  tlie  rainfall  at  the  various  stations  has  approximately  like  charac- 
istics  when  expressed  in  relation  to  its  normal  although  the  actual  rain  in  inches 
at  the  several  stations  may  be  very  different. 


42 


WATER   RESOURCES   OF    CALIFORNIA. 


PLATE  VI. 

'                                        SACRAMENTO   RIVER   NEAR  RED  BLUFF 

1895-1925 

2. 

,           50           75           100       ,.    \        150           r75          200          225          250          275          300            | 

22( 

Feh.2,i915^ I 

Teb.3.l909 

18 

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10 

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..•••;••••' 

6 

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t'f. 

*-•  :, 

;  .* 

Rood  fiow  45300  secft-x^    -1 
Index  567          JX  1 

• 

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MOKELUMNE   RIVER   NEAR  CLEMENTS 

1904-1925 

o 

2 

5           50           75           100          125           150           175          200         225         250          275          300 

o 

0) 

16 
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,-Jon.'  30,1911 

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SAN   JOAQUIN   RIVER  NEAR   FRIANT 

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Progressive  rainfall  index 

Progressive  Rainfall  Index  at  Time  of  Flood  Flow 

ALL    FLOODS    OF  RECORD  PLOHED 

THE    CONTROL    OF   FLOODS   BY   RESERVOIRS.  43 

producing  capacity  of  weather  sequences,  nevertheless,  it  was  found 
that  there  are  limiting  values  with  which  flows  of  the  various  sizes 
occur  and  that  the  probability  of  their  occurrence  with  values  beyond 
these  limits  is  too  remote  for  practical  considerations.  To  define  these 
limiting  values  of  index  for  the  various  size  flows,  an  analysis  was  made 
of  the  frequency  with  which  flows  of  greater-than-specified  sizes  have 
occurred  in  the  past  with  varying  index  values.  The  results  of  this 
analysis  for  the  four  illustrative  streams  are  drafted  on  Plates  VII, 
Vlli  and  IX,  "Relation  of  Progressive  Rainfall  Index  to  Flood 
Occurrence."  The  construction  of  these  plates,  as  well  as  the  analyses 
upon  which  they  are  based,  is  identical  to  that  of  Plates  IV  and  V, 
"Relation  of  Time  of  Year  to  Flood  Occurrence,"  except  that  values  of 
the  progressive  rainfall  index  are  substituted  for  days  of  the  year. 

On  the  diagrams  of  Plates  VII,  VIII  and  IX,  each  pair  of  curves,  one 
dotted  and  one  full-line,  represents  a  specified  rate  of  flow\  For  con- 
venience in  comparison  between  streams,  the  rate  of  flow  is  expressed  in 
relation  to  that  of  a  once-in-25-year  flood.  A  conversion  table  to  second- 
feet  is  in  the  upper  right  corner  of  each  diagram.  The  full-line  curves 
approximate  the  trend  of  the  data  expressing  the  probable  frequency 
of  flows  in  excess  of  their  size  that  occur  with  smaller  values  of  the  pro- 
gressive rainfall  index  than  indicated  on  the  vertical  scale.  The  dotted- 
line  curves  express  the  probable  frequency  of  flows  in  excess  of  their 
size  that  occur  with  greater  values  of  the  index  than  indicated  on  the 
vertical  scale.  As  in  the  diagrams  constructed  in  a  corresponding  way 
to  determine  the  limiting  dates  of  the  flood  season  (Plates  IV  and  V), 
the  curves  are  w^ell  defined  by  the  data  only  for  the  smaller  flows  for 
which  more  data  are  contained  in  the  stream  flow  records.  The  curves 
for  the  larger  flows  were  drafted  largely  by  comparison  with  the  better 
defined  curves  for  the  smaller  ones.  Although  the  analysis  delineated 
on  Plates  VII,  VIII,  and  IX  can  not  be  said  to  be  exact  because  of  the 
limited  amount  of  information  relating  to  the  larger  floods,  an  examina- 
tion of  the  similar  trend  of  the  data  on  the  several  streams  investigated, 
is  convincing  that  the  results  are  substantially  correct  to  the  extent 
that  the  future  will  repeat  the  past. 

By  way  of  illustrating  the  interpretation  of  these  plates,  reference  is 
made  to  the  upper  figure  on  Plate  VII  which  shows  the  relation  of  the 
progressive  rainfall  index  to  flood  occurrence  in  the  Sacramento  River 
near  Red  Bluff.  Following  up  the  vertical  line  labeled  1  on  the  hori- 
zontal frequency  scale  to  intersection  with  the  pair  of  50  per  cent 
curves,  it  is  seen  that  the  intersection  with  the  full-line  curve  is  opposite 
a  value  of  58  on  the  scale  of  progressive  rainfall  index  to  the  left. 
This  means  that,  on  one  day  in  100  years,  flows  will  probably  occur  in 
excess  of  50  per  cent  of  a  once-in-25-year  flood  with  a  progressive  rain- 
fall index  value  smaller  than  58.  Following  the  vertical  line  labeled 
1  on  the  horizontal  scale  to  intersection  with  the  dotted-line  curve,  it 
is  seen  that  the  intersection  lies  opposite  188  on  the  scale  of  progres- 
sive rainfall  index  to  the  left.  This  means  that,  on  one  day  in  100  years, 
flows  will  probably  occur  in  excess  of  50  per  cent  of  a  once-in-25-year 
flood  with  a  progressive  rainfall  index  value  greater  than  188.  The 
values  58  and  188  are  then  the  limiting  values  with  which  such  floods 
occur  with  a  probability  of  exceptional  behavior  of  one  day  in  a  hun- 
dred years. 


44 


WATER   RESOURCES   OF    CALIFORNIA. 


PLATE  vn. 


300 


SACRAMENTO  RIVER  NEAR  RED  BLUFF 


=  200  £ 


a>  — 


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Number  of  days  in  100  years  on  whicii  flows  are  exceeded 


Relation  of  Progressive  Rainfall  Index  to  Flood  Occurrence 


CURVES    SHOW   NUMBER    OF   DAYS   IN   100   YEARS    ON 
WHICH   FLOWS   OCCUR   IN   EXCESS  OF  SPECIFIED   SIZE 
WITH    VALUES    OF    PROGRESSIVE    RAINFALL     INDEX 
GREATER    AND    LESS   THAN    INDICATED.  ^ 

Flows  expressed  in  percent  of  greatest  daily  rate  of  flow  of  once-in-25-^ear  flood 


THE    CONTROL   OF   FLOODS   BY   RESERVOIRS. 


45 
PLATE  VIII. 


Progressive   rainfall  index                                             Progressive    rainfall  index 

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000 

Relation  of  Progressive  Rainfall  Index  to  Flood  Occurrence 

CURVES   SHOW  NUMBER    OF  DAYS   IN  100  YEARS    ON 

WHICH    FLOWS  OCCUR  IN   EXCESS  OF  SPECIFIED   SHE 

WITH    VALUES    OF    PROGRESSIVE    RAINFALL    INDEX 

GREATER    AND    LESS   THAN    INDICATED. 

riows  expressed  m  percent  of  greatest  daily  rate  of  flow  of  once-in-25->ear  flood 

46 


WATER   RESOURCES   OF    CALIFORNIA. 


PLATE    IX, 


400 

SAN  JOAQUIN  RIVER 

NEAR 

FRIANT 

1 

U 

--    .-1     1   :.  1  '1 

r 

'  i 

Symbol 

M  11 

1    1   1  1  : 

Stofonccrv 

Second  feel 

V 

30 
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60 
70 

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14.200 
17.800 
21.400 
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1       i     1    '  ill 

300 

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Number  of  da^^s  in  100  years  on  which  flows  are  exceeded 


Relation  of  Progressive  Rainfall  Index  to  Flood  Occurrence 


CURVES    SHOW  NUMBER   OF  DAYS   IN  100   YEARS    ON 

WHICH   FLOWS  OCCUR  IN   EXCESS  OF  SPECIFIED  SIZE 

WITH    VALUES    OF    PROGRESSIVE    RAINFALL    INDEX 

GREATER     AND    LESS   THAN    INDICATED. 

Flows  expressed  in  per  cent  of  greatest  daily  rate  of  flow  of  once- m- 25 -year  flooa 


THE    CONTROL   OF   FLOODS   BY   RESERVOIRS.  47 

The  data  from  which  these  curves  (Plates  VII,  VIII  and  IX)  were 
constructed  are  largely  included  within  frequencies  greater  than  four 
days  in  a  hundred  years.  The  frequency  of  four  days  in  a  hundred 
years  represents  one  occurrence  during  the  period  of  25  years  of 
measurement,  the  length  of  the  longer  records.  Knowledge  of  expec- 
tancies had  records  been  kept  for  greater  lengths  of  time,  may  be 
obtained  by  extending  these  curves  into  the  zones  of  smaller  frequencies. 
In  so  doing,  information  is  gained  of  the  probability  of  flood  occurrence 
with  indices  greater  or  less  than  the  limiting  values  shown  in  the  records 
themselves.  The  limiting  values  betM^een  which  any  specific  flow  occurs 
are  indicated  on  the  diagrams  by  the  extremities  of  the  intercept  on  any 
vertical  line  made  by  the  two  curves  of  the  pair  representing  that 
specific  flow.  The  limiting  values  of  the  index  are  read  on  the  index 
scale  to  the  left,  opposite  the  extremities  of  the  intercept.  The  frequency 
of  greater  flows  occurring  with  larger  or  smaller  values  of  the  index 
than  there  indicated,  is  read  on  the  horizontal  frequency  scale  where  it 
is  cut  by  the  vertical  intercepted  by  the  pair  of  curves.  The  intercept 
on  the  vertical  at  the  extreme  left  of  the  diagrams,  labeled  0.1  on  the 
frequency  scale,  gives  the  limiting  values  of  indices  with  which  flows 
greater  than  specified  will  probably  occur  either  with  an  index  greater 
than  the  upper  limit  or  with  an  index  smaller  than  the  lower  limit  except 
on  one  day  in  a  thousand  years.  The  intercepts  on  verticals  represent- 
ing greater  frequencies  of  exceptional  behavior  become  smaller  as  the 
frequencies  become  larger.  These  smaller  intercepts  indicate  a  lesser 
range  of  index  values  with  which  flows  occur  greater  than  specified. 

The  following  tables  set  forth  the  range  of  index  values  indicated  by 
Plates  VII,  VIII  and  IX,  within  which  floods  greater  than  various 
specific  sizes  will  probably  occur  on  the  four  illustrative  streams.  The 
maximum  and  minimum  values  are  tabulated  for  several  different  fre- 
quencies of  exceptional  occurrence. 

It  may  be  observed,  on  reviewing  these  tables,  that  the  smallest  limit- 
ing value  of  the  progressive  rainfall  index  therein  is  28  and  the  largest 
is  293,  both  for  the  San  Gabriel  River.  The  extreme  values  for  the 
other  streams  are  51  and  239  on  the  Mokelumne,  43  and  211  on  the  Sac- 
ramento, and  46  and  189  on  the  San  Joaquin  River.  The  least  values 
Avith  which  rain-water  floods  of  corresponding  size  (equal  per  cent  of 
once-in-25-year  flood)  occur,  differ  not  more  than  33  points  on  the  four 
illustrative  streams  while  the  maximum  values  differ  not  more  than  75 
points.  The  smallest  floods  tabulated  occur  with  minimum  indices 
from  15  to  66  points  smaller  than  the  minimum  indices  for  the  largest 
floods  and  with  maximum  indices  from  14  to  115  points  larger  than  the 
maximum  indices  for  the  largest  floods.  For  decreasing  the  probability 
from  one  day  in  10  years  to  one  day  in  1000  years  that  flows  in  excess 
of  those  specified  will  not  occur  with  either  smaller  or  larger  values  of 
the  index  than  indicated,  the  minimum  value  of  the  index  may  be 
reduced  as  much  as  58  points  and  the  maximum  value  increased  as  much 
as  87  points.  The  range  of  index  values  with  which  floods  occur  from 
rapidly  melting  snow  is  seen  to  be  less  variable  than  for  rain-water 
floods.  Of  the  two  illustrative  streams  having  snow-water  floods,  the 
smallest  value  of  the  index  with  which  they  occur  is  61  and  the  largest 
is  163.  The  minimum  values  on  the  two  streams  differ  not  more  than 
16  points  and  the  maximum  not  more  than  15  points. 


48 


WATER   RESOURCES   OF    CALIFORNIA. 


SACRAMENTO  RIVER. 

LIMITING  VALUES  OF  PROGRESSIVE  RAINFALL  INDEX  BETWEEN 
WHICH  FLOODS  OCCUR. 


Size  of  flood  near 

Red  Bluff- 
greatest  daily  rate 
of  flow 


Minimum  index  values 


Maximum  index  values 


Frequency  with  which  flows  occur  with 
progressive  rainfall  index*  less  than 


Frequency  with  which  flows  occur  with 
progressive  rainfall  index*  greater  than 


values  tabulated 

values  tabulated 

In  per 

In 

cent  of 

1               1 

once-m- 

second- 

One  day 

One  day 

One  day  One  day 

One  day 

One  day 

One  day  One  day  ■  One  day  |  One  day 

25-year 

feet, 

in  1000 

in  100 

in  50        in  25 

in  10 

in  1000 

in  100       in  50        in  25        in  10 

flood 

years 

years 

years    |    years 

years 

years 

years       years    ;    years       years 

30 

74,700 

43 

48 

52 

57 

64 

211 

203 

198 

192 

183 

40 

99,600 

47 

53 

57 

62 

71 

204 

196 

191 

185 

173 

50 

124,500 

1       51 

58 

62 

69 

80 

198 

188 

182 

174 

160 

60 

149,400 

55 

63 

69 

77 

91 

192 

179 

171 

161 

143 

70 

174,300 

58 

69 

76 

86 

103 

187 

169 

160 

148 

125 

•At  Red  Bluff  rainfall  station. 


MOKELUMNE  RIVER. 

LIMITING  VALUES  OF  PROGRESSIVE  RAINFALL  INDEX  BETWEEN 
WHICH  FLOODS  OCCUR. 


Size  of  flood  near 

Clements — 

greatest  daily  rate 

of  flow 


In  per 
cent  of 
once-in- 
25-year 
flood 


Id 
second- 
feet 


Minimum  index  values 


Maximum  index  values 


Frequency  with  which  flows  occur  with 

progressive  rainfall  index*  less  than 

values  tabulated 


Frequency  with  which  flows  occur  with 

progressive  rainfall  index*  greater  than 

values  tabulated 


One  day 

One  day 

One  day 

in  1000 

in  100 

in  50 

years 

years 

years 

51 

56 

59 

57 

65 

69 

63 

72 

78 

69 

80 

88 

75 

90 

100 

68 

71 

72 

84 

87 

89 

One  day 
in  25 

One  day 
in  10 

One  dav 
in  1000 

years 

years 

years 

One  day 

One  day 

One  day 

in  100 

in  50 

in  25 

years 

years 

years 

227 

221 

214 

212 

205 

197 

197 

190 

180 

184 

176 

165 

169 

160 

147 

162 

161 

160 

153 

112 

150 

One  day 
in  10 
years 


30 
40 
50 
60 
70 


30 
40 


Raln-Water  Floods. 


5,300 
7,100 
8,900 
10.700 
12,500 


5,300 
7,100 


64 
75 
85 
97 
112 


71 

239 

84 

225 

98 

211 

113 

199 

187 

Snow-Watcr  Floods. 


163 
154 


202 
183 
164 
146 


158 
146 


*At  Elcctra  ramfall  station. 


THE    CONTROL   OP   FLOODS   BY    RESERVOIRS. 


49 


SAN  JOAQUIN  RIVER. 

LIMITING  VALUES  OF  PROGRESSIVE  RAINFALL  INDEX  BETWEEN 
WHICH  FLOODS  OCCUR. 


Size  of  flood  near 
Friant— 

Minimum  index  values 

Maximum  index  values 

greatest  daily  rate 
of  flow 

Frequency  with  which  flows  occur  with 

progressive  rainfall  index*  less  than 

values  tabulated 

Frequency  with  which  flows  occur  with 
progressive  rainfall  index*  greater  than 

values  tabulated 

In  per 

In 

sejond- 
feet 

cent  of 
once-in- 

25-year 

One  day 
in  1000 

One  day 
in  100 

One  day 
in  50 

One  day 
in  25 

One  day 
in  10 

One  day 
in  1000 

One  day 
in  100 

One  day 
in  50 

One  day 
in  25 

One  day 
in  10 

flood 

years 

years 

years 

years 

years 

years 

years 

years 

years 

years 

Rain-Water  Floods. 

30 
40 
50 
60 
70 

10.700 
14,200 
17,800 
21,400 
24,900 

415 
54 
Gl 
67 

72 

53 
61 
68 
75 
81 

58 
66 
73 
80 

87 

63 
72 

79 
87 
96 

73 
83 
93 
103 
117 

189 
185 
181 
178 
175 

185 
180 
176 
172 
108 

182 
177 
173 
168 
162 

178 
173 
167 
161 
153 

170 
162 
154 
144 
133 

Snow-Water  Floods. 

30 
40 
50 
60 

10,700 
14,200 
17,800 
21,400 

61 
70 
78 
85 

63 
72 
81 
89 

64 
73 
83 

92 

66 
75 

85 
90 

69 
79 
90 
105 

149 
142 
137 
133 

147 
139 
133 
128 

146 
138 
132 
126 

145 
136 
130 
123 

143 
134 
126 
116 

*At  Fresno  rainfall  station. 


SAN  GABRIEL  RIVER. 


LIMITING  VALUES   OF  PROGRESSIVE  RAINFALL  INDEX  BETWEEN 
WHICH  FLOODS  OCCUR. 


Size  of  flood  near 

Minimum  index  values 

Maximum  index  values 

Azusa — 

greatest  daily  rate 

of  flow 

Freq 

lencv  with  which  flows  occur  with 

Freq 

uency  with  which  flows  occur  with 

progressive  rainfall  index*  less  than 
values  tabulated 

lirogressive  rainfall  index*  greater 
values  tabulated 

than 

In  per 

In 

cent  cf 

once-in- 

second- 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

25-year 

feet 

in  1000 

in  100 

mSO 

in  25 

in  10 

in  1000 

in  100 

in  50 

in  25 

in  10 

flood 

years 

years 

years 

years 

years 

years 

years 

years 

years 

years 

10 

1,900 

28 

35 

39 

45 

55 

293 

280 

274 

266 

253 

20 

3,800 

36 

43 

48 

53 

64 

278 

261 

2,53 

242 

222 

30 

5,800 

43 

50 

56 

63 

77 

264 

246 

235 

222 

198 

40 

7,700 

49 

57 

62 

72 

93 

251 

231 

219 

204 

177 

50 

9,600 

55 

63 

71 

83 

113 

240 

217 

203 

186 

153 

60 

11,500 

59 

69 

78 

95 

229 

202 

188 

169 

70 

13,400 

64 

75 

86 

111 

220 

188 

172 

151 

*At  Claremont  rainfall  station. 


Most  favorable  value  of  progressive   rainfall    index  for  flood   occurrence. 

It  has  been  observed  that  there  are  limiting  values  of  the  progressive 
rainfall  index  with  which  floods  occur.  Plates  VII,  VIII  and  IX, 
"Relation  of  Progressive  Rainfall  Index  to  Flood  Occurrence,"  deline- 
ate the  frequency  of  the  exceptional  occurrence  of  flows  outside  of  either 
of  these  limits.  Pairs  of  curves  are  drafted  on  these  plates,  one  dotted 
and  one  full-line,  representing  this  exce])tional  behavior  of  flows  exceed- 
ing specified  amounts.    The  full-line  curves  show  the  probable  fretiuency 

4—52411 


50 


WATER    RESOURCES    OF    CALIFORNIA. 


of  occurrence  of  greater-thaii-specified  flows  with  index  values  smaller 
than  indicated,  while  the  dotted-line  curves  show  the  probable  frequency 
of  occurrence  with  index  values  larger  than  indicated  on  the  vertical 
scale.  The  two  curves  of  eacli  pair  approach  each  other  as  these  fre- 
(piencies  increase,  until  their  intersection  indicates  a  value  of  the  pro- 
gressive rainfall  index  witli  which  greater-tlian-specified  flows  occur 
equally  frecpient  with  either  smaller  or  larger  values  of  the  index.  This 
is  the  index  value  with  which  flows  greater  than  specified  occur  most 
frequently  since  the  frequency  of  occurrence  with  either  smaller  or 
hirger  values  is  the  same.  Therefore,  the  values  of  the  progressive  rain- 
fall index  indicated  by  the  intersections  of  these  pairs  of  curves,  are 
the  most  favorable  values  for  flood  occurrence. 

The  following  table  contains  tlie  most  favorable  index  values  for  the 
occurrence  of  flows  of  greater-than-si)ecified  sizes  on  the  Sacramento, 
Mokelumne,  San  Joaquin  and  San  Gabriel  rivers  as  taken  from  Plates 
VII,  VIII  and  IX.  It  may  be  noted  that  the  values  range  from  114  to 
]43  for  rain-water  floods,  being  least  for  the  Sacramento  River  and 
largest  for  the  San  Gabriel.  On  the  San  Joaquin  River  the  values  for 
the  several  sizes  vary  only  one  ])oint  while  on  the  ^lokelumne  the 
\ariance  is  two,  on  the  Sacramento  four  and  on  tlie  San  Gabriel  twelve 
))oints.  The  most  favorable  values  for  snow-Avater  flows  on  the  ]\Ioke- 
lumne  and  San  Joaquin  rivers,  are  smaller  than  for  rain-water  flows. 
On  the  Mokelumne  tliis  value  is  118,  while  on  the  San  Joariuin  it  is 
110-111. 


MOST  FAVORABLE  VALUE  OF  PROGRESSIVE  RAINFALL   INDEX  FOR 

FLOOD  OCCURRENCE. 


Size  of  flood 

Sacramento 
River 

Mokelumne  River 

San  .Joaquin  River 

III  per  cent  of 

greatest  daily  rate 

of  flow  of 

once-in-25-ycar 

flood 

Rain-water 
floods 

Snow-water 
Hoods 

Rain-water 
floods 

Snow-water 
floods 

San  Gabriel 
River 

10 

143 

20 

136 

30 
40 
50 

iis 

117 
117 
114 
114 

127 
128 
129 
129 
129 

118 
118 

124 
124 
124 
124 
12.5 

no 

110 

no 
111 

137 
134 
134 

60 

134 

70 

133 

Relation  of  flood   occurrence  to  season's  run-off. 

It  has  been  i)ointed  out  througli  analyses  of  .stream  flow  records,  that 
the  mo.st  favorable  time  for  flood  occurrence,  excei)t  from  melting  snow, 
is  in  mid-winter.  Thus,  it  would  be  exi)ected  that  the  largest  and 
heaviest  floods  occur  during  the  middle  of  the  rainy  season  followed 
by  a  considerable  part  of  the  season's  total  i)r('cipitation  and  hence  a 
considerable  part  of  the  season's  run-off.  Therefore,  since  large  floods 
usually  occur  in  seasons  of  greater  than  normal  run-oft',  tlie  stream 
flow  subsequent  to  them  should  be  a  substantial  fraction  of  that  for 
a  normal  .season. 

The  following  table  presents  the  nin-olf  in  the  Sacramento, 
Mokelumne,   San   Joa(piin   and   San   Gabriel    rivers  sub.sequent    to   the 


THE    CONTROIi    OF    FLOODS    BY    RESERVOIRS.  51 

largest  floods  on  record.  The  run-oft'  is  expressed  in  per  cent  of  the 
total  run-off  for  an  average  season.  It  may  be  noted  that  the  run-off 
subsequent  to  the  largest  floods  of  record  on  the  Sacramento  River 
averaged  80  per  cent  of  the  total  for  a  normal  season,  on  the  Mokelumne 
and  San  Joaquin,  following  rain-water  floods,  106  and  120  i)er  cent, 
respectively,  and  on  the  San  Gabriel  129  i)er  cent  of  the  total  run-off 
of  a  normal  season.  The  run-off  subsequent  to  the  largest  snow-water 
Hoods  on  the  Mokelumne  and  San  Joaquin  rivers  was  44  and  48  per 
cent,  respectively,  of  the  total  for  a  normal  season.  These  values 
varied  considerably  with  the  diff'erent  floods.  On  the  Sacramento, 
INIokelumne  and  San  Joaquin  rivers  the  minimums  were  about  half  the 
average  values,  but  on  the  San  Gabriel  it  was  about  a  third  of  the 
average.  It  is  seen  that,  for  the  most  ]^art,  a  very  substantial  amount  of 
run-off'  follows  large  floods,  even  the  snow-water  floods  tliat  occur  late 
in  the  season. 


I 


52 


WATER    RESOURCES   OF    CALIFORNIA. 


RUN-OFF  SUBSEQUENT  TO  LARGEST  FLOODS  OF  RECORD. 


Sacramento  River 

Moicelumne  River 

Rain-water  flood 

Snow-water  floods 

Mean 

Subsequent 

daily 
flow  in 
second- 
feet 

Date  of  flood 

run-off  in 
I)er  cent 

Mean 
daily 

Subsequent 
run-off  in 

Mean 
daily 

Subsequent 
run-off  in 

flow  in 

Date  of  flood 

per  cent 

flow  in 

Date  of  flood 

per  cent 

second- 

of  mean 

second- 

of  mean 

feet 

seasonal- 

feet 

seasonal' 

254,000 

Feb.     3, 

1909 

79.9 

16,700 

Jan.  30, 

1911 

•149.1 

8.740 

June  12,  1906 

•50.9 

249,000 

Feb.    2, 

1915 

93.1 

15,310 

Mar.  19, 

1907 

136.9 

8,030 

Juno  18,  1911 

27.4 

196.000 

Mar.  20 

1907 

63.3 

11,100 

Jan.  26, 

1914 

101.3 

7,970 

June    3,  1922 

•30,8 

188,000 

Jan.   16 

1909 

114.7 

10,400 

Jan.   14, 

1909 

•118.3 

7,900 

June  12, 1911 

36.5 

188.000 

Feb.  10, 

1904 

121.7 

9,850 

Feb.  21, 

1914 

90.3 

7,880 

June    0.  1911 

45.2 

177,000 

Jan.  21, 

1909 

101.5 

9,700 

Feb.     0, 

1925 

80.8 

7,770 

May  31,  1922 

37.5 

176,000 

Feb.  25, 

1917 

44.9 

9,250 

Jan.     1, 

1914 

114.6 

7,750 

June    1,  1915 

30.3 

100,000 

Feb.  21, 

1914 

05.4 

8,400 

,Ian.  21, 

1909 

110.9 

7,670 

May  18,  1922 

53.9 

1.51,000 

.Jan.     1, 

1914 

*113.1 

8,040 

Mar.  20, 

1916 

79.5 

7,600 

June  16,  1906 

•45.0 

1. 5 1,000 

Feb.  24, 

1902 

x,58.4 

7,860 

Feb.     2, 

1907 

107.2 

7,550 

June  10,  1917 

24.0 

147,000 

Mar.    8, 

1904 

91.3 

7,750 

Mar.  31, 

1906 

119.0 

7,500 

May  24,  1911 

•58.3 

140,000 

Feb.  10, 

1902 

X80.9 

7,610 

Mar.  23, 

1907 

*127.0 

7,480 

July     4,  1906 

22.4 

137,000 

Mar.  ;?1, 

1906 

50.0 

7,47,0 

Jan.  22 

1914 

100.8 

0,960 

June  22,  1906 

37.6 

136,000 

Jan.   19, 

1906 

93.5 

7,350 

.Jan.   18, 

1921 

85.1 

6,900 

June    2,  1907 

57.6 

134,000 

Feb.     4, 

1907 

99.5 

7,210 

Mar.    7, 

1911 

'126.9 

0,850 

June  20,  1906 

40.6 

131,000 

Jan.  25, 

1903 

63.6 

7,200 

Nov.  21 

1909 

97.4 

6,800 

June    2,  1909 

32.6 

130,000 

Mar.    7, 

1911 

50.6 

7,060 

Feb.  11 

1919 

.57.8 

6,7,50 

May    7,  1906 

92.4 

128.000 

Jan.   27, 

1896 

77.7 

6,960 

Jan.   19 

1906 

143.9 

6,700 

June    8,  1915 

X19.2 

123,000 

Mar.    8 

1900 

.34.6 

6.940 

Mar.  12 

1918 

.50.1 

6,640 

May    9,  1906 

x89.5 

122,000 

Jan.  22 

1914 

89.6 

6,910 

Apr.  16 

1925 

*51.8 

0,6.30 

May  13,  1915 

48.7 

Average  va 

lie 

79.6 

105.8 

44.0 

San  Joaquin  River 

San  Gabrit 

1  River 

Rain-water  floods 

Snow-water  flood 

s 

Mean 

Subsequent 

Mean 
daily 
flow  in 

Date  of  flood 

Subsequent 
run-off  in 
percent 

Mean 
daily 
flow  in 

Date  of  flood 

Subsequent 
run-off  in 
per  cent 

daily 
flow  in 
second- 
fee  t 

Date  of  flood 

run-off  in 
per  cent 
of  mean 

second- 

of  mean 

second- 

of  mean 

feet 

seasonal" 

feet 

seasonal' 

38,800 

Jan.  31, 

1911 

157.5 

23,100 

June  13 

1911 

63.9 

22,300 

Jan.   18, 

1910 

125.3 

27,900 

Dec.  31, 

1909 

84.0 

22,800 

June    4 

1909 

•51.0 

16,000 

Dec.  19, 

1921 

253.6 

26,800 

.Jan.    14, 

1909 

•132.4 

21,500 

June  10 

1911 

*,50.0 

12,.500 

Jan.     1, 

1910 

60.0 

26,800 

Dec.  10, 

1909 

91.2 

19,,500 

July     7 

1911 

27.8 

11,800 

Feb.  20. 

1914 

119.9 

24,700 

Jan.  26, 

1914 

120.7 

16,700 

June    5, 

1922 

45.9 

11,130 

Mar.  12, 

1905 

70.7 

18,900 

.Jan.  21, 

1909 

•127.5 

16,200 

May  22 

1911 

•90.1 

9,430 

Mar.  20, 

1906 

83.4 

18,800 

Mar.    8, 

1911 

142.9 

16,200 

June    6 

1911 

75.8 

9,160 

Mar.  10, 

1911 

86.5 

13,000 

Mar.  10, 

1911 

•140.2 

16,200 

May    8 

190<.» 

"80.5 

9,150 

Jan.   20. 

1914 

165.2 

12, .500 

Feb.  12, 

1909 

•119.9 

15,700 

June    2 

1914 

55.1 

8,200 

Feb.     9, 

1922 

135.6 

11,700 

Feb.  21. 

1917 

82.1 

15,300 

June    5 

1912 

19.4 

8,020 

Mar.  12 

1906 

•127.4 

11,000 

Apr.     6, 

1911 

126.2 

14,900 

June  15 

1909 

•35.4 

7,940 

Jan.   27, 

1916 

96.7 

11,000 

Jan.   18, 

1910 

126,7 

14,700 

June  27 

1911 

•39.2 

7,100 

Feb.     7, 

1909 

88.6 

11,000 

Mar.  21, 

1916 

104.0 

14,700 

May  31, 

1922 

54.9 

6,810 

Mar.    5, 

1907 

142.5 

10,900 

Oct.     2, 

1918 

02.5 

14,000 

June  24 

1909 

•20.1 

5,920 

Apr.     1, 

1903 

41.1 

10,700 

Jan.  2.5, 

1911 

105.8 

14,000 

June  11 

1909 

42.1 

5,900 

Dee.  27, 

192! 

208.2 

10,400 

Apr.     5, 

1914 

103.1 

13,800 

June    9, 

1915 

•30.9 

5,260 

Jan.  29. 

1911 

164.8 

9,910 

Feb.  21, 

1914 

119.0 

13,500 

June     1, 

1915 

x44.5 

,5,110 

Jan.    18, 

1914 

187.8 

9,150 

Mar.    5, 

1916 

112.8 

13,400 

June  10, 

1917 

34.2 

5,030 

Mar.  11, 

1918 

58.0 

8.900 

Jan.   18, 

1914 

132.2 

13,400 

May  25, 

1922 

62.2 

4,670 

Jan.   10, 

1907 

214.1 

8,720 

Mar.   4, 

1911 

146.0 
120.2 

13,300 

July  18 

1911 

15.2 
47.8 

4,220 

Jan.  31, 

1911 

156.8 
129.3 

'  Mean  seasonal  run-olT  of  Sacramento  IViver  near  Red  Bluff  (50  yr.  mean)  9,929,000  acre-feet. 
"  .Mean  seasonal  run-olT  of  Mokelunuie  Hiver  near  Olcnients  (50  yr.  mean)  898.000  acre-feet. 
» Mean  seasonal  run-olT  of  .'-!;in  .loiuiuin  Hiver  near  Friant  (50  yr.  mean^  2.057,000  aere-fect. 
*  Mean  seasonal  run-off  of  San  Cial)riel  Hiver  near  Azusa  (50  yr.  mean)  147,(K)(I  acre-feef . 
•Second  day  after  flood  to  October  1. 
xThird  day  after  flood  to  October  1. 
All  other  values  of  run-off  Hulweiiuent  to  flood  are  from  first  day  after  flood  to  October  1 . 


THE    CONTROL    OF    FLOODS    BY    RESERVOIRS.  53 

CHAPTER  IV. 


RESERVOIR  SPACE  REQUIRED  TO  DETAIN  EXCESS  FLOOD 

FLOWS. 


Source  of  infortnation. 

Of  all  information  t'oncei-ning  Hoods,  that  most  imi)ortant  to  their 
control  by  reservoirs  is  the  volume  of  water  contained  in  the  excessive 
rates  of  tlow.  This  is  the  volume  that  must  be  detained  in  reservoirs 
if  the  downstream  flow  is  to  be  limited  to  reasonable  rates.  Informa- 
tion concernino-  the  volume  tliat  must  be  so  detained  is  contained  in 
the  records  of  stream  measurement.  Althoug'h  the  i)eriod  of  measure- 
ment in  California  is  too  brief  for  direct  disclosure  of  either  the 
largest  floods  that  may  occur  or  the  length  of  the  intervals  between 
them,  nevertheless,  within  these  records  is  the  sum  total  of  accurate 
knowledge  of  the  volume  of  flood  flow.  Other  information,  at  best,  is 
indirect  and  very  approximate.  Flood  estimates  based  on  high-water 
marks,  on  the  memory  of  old  inhabitants  or  rates  of  rainfall  that  have 
occurred  in  other  localities,  contain  many  elements  of  uncertainty. 
The  stream-flow  measurements  themselves  are  the  only  direct  and 
definite  information  on  the  volume  of  flood  flow.  This  study,  therefore, 
is  confined  to  their  analj^sis. 

Continuous  stream  measurement  in  California  was  started  with  the 
establishment  of  the  first  gaging  station  at  Jelly's  Ferry  on  the  Sacra- 
mento River  in  1895.  Since  then  many  other  stations  have  been  estab- 
lished on  the  larger  streams.  At  present,  about  250  stations  are  main- 
tained by  the  United  States  Geological  Survey  and  the  State  of  Cali- 
fornia in  cooperation.  From  the  continuous  records  kept  at  these 
stations,  the  United  States  Geological  Survey  publishes  in  its  water- 
supply  papers,  tables  of  the  average  daily  stream  flow  past  each  one 
of  these  points  of  measurement.  The  published  tables,  together  with 
those  in  preparation  for  publication,  have  been  used  in  the  computations 
of  this  bulletin. 

Method  of  analysis. 

Since  the  stream-flow  records  cover  too  short  a  time  to  include  the 
maximum  flood  that  might  occur,  it  is  desirable  to  ascertain  the  rela- 
tion between  the  volume  of  flow  and  frequency  of  its  occurrence  as 
disclosed  by  the  many  smaller  floods  observed  during  the  period  of 
record.  To  ascertain  the  volume  of  water  contained  in  the  excessive 
rates  of  flood  flow,  the  records  on  twenty  streams  of  the  State  that 
have  been  measured  from  seventeen  to  thirty  j^ears  were  assembled  and 
the  volume  of  w^ater  contained  in  every  flood  in  excess  of  certain  speci- 
fied rates  of  flow  was  computed.  These  are  the  volumes  of  water  that 
would  have  had  to  be  detained  in  reservoirs  to  have  reduced  the 
floods  of  record  to  the  specified  rates  of  maximum  flow  through  reser- 
voir control.  The  following  table  enumerates  the  streams  whose  records 
were  analysed,  the  names  of  the  stream-gaging  stations  and  the  i)oi-iod 
of  record : 


54 


WATER    RESOURCES   OF    CALIFORNIA. 


LIST  OF  STREAM  FLOW  RECORDS  ANALYZED  FOR 
FLOOD  CHARACTERISTICS. 


Stream 

Gaging  station 

Drainage 
area  in 
square 
miles 

Period  of  record 

Number 
of  years 
of  record 

Jellv's  Ferry 

Red  Bluff 

9.093 

9.258 

3.627 

1.200 

262 

1.919 

534 

632 

394 

983 

973 

1,543 

1,054 

1,020 

1.034 

1,631 

1,694 

514 

264 

2,410 

577 

636 

655 

214 

189 

199 

Apr.  29.  1895-Jan.  31,  1902\ 
Feb.     1,  1902-Oct.     1,  19251 
•Ian.     1,  1902-Oct.     1,  1925 
July     1.  1903-Oct.     1,  1925 
Oct.     8,  1904-Oct.     1.  1925 
Nov.    4,  1904-Oct.     1.  1925 
Oct.  20,  1907-Oet.     1.  1925 

30.4 

2J  7 

Yuba  River 

Smartsville 

Van  Trent 

22.3 
21.0 

20.9 

Michigan  Bar 

Clements 

17  9 

Mokelumnc  River 

Oct.  28,  1904-Oct.     1,  1925              20.9 
.Ian.     1,  1907-Oct.     1,1925              18.7 

May  19,  1903-May    1,  1916;             „  - 
May    1   1916-Oct.     1,  1925  , 

.\ug-  30.  1895-Oct.     1,  1925              30.1 

Apr.     6.  1901-Nov.  30.  1913: 

Nov.  28,  191.5-Nov.,       19T2}\            22.5 

Nov..       1922-Oct.     1,1925! 

San  Joaquin  River 

Friant 

Oct.   18,  1907-Oct.     1,  1925               18.0 

Sanger 

Three  Rivers  

Sept.    3.  189,5-Oct.     1,  1925              30.1 

Apr.  29,  1903-Oct.     1,  1925              22.4 

Tule  River             

May    1,  1901-Oct.     1,1925  i            24.4 
Jan.     1,  1896-Oct.     1.  1925  1            29  8 

Jan.  30.  1901-Oct.     5.  1912               ,.  , 
Jan.     1,  1920-Oct.     1,1925 

Orland 

Piitah  Creek       

Oct.     1,  1905-Oct.     1.  1925  ;            20.0 

San  Gabriel  River 

Azusa 

Aug.    1,  1895-Oct.     1,  1925  |            30.2 

Juiv     1.  1896-Oct.     1,  1914\             „q  , 
Oct.     I,  1914-Oct.     1,1925'! 

After  computing  the  volume  of  water  in  all  flow.s  exceeding;  certain 
,si)eeified  rates,  determination  was  made  for  each  successive  day  of  every 
flood  of  the  em])ty  reservoir  s])ace  that  would  have  been  needed  to 
have  absorbed,  through  the  remainder  of  the  flood,  all  water  in  excess  of 
the  several  s])ecified  rates  of  flow.  Counts  were  made  in  each  set  of 
computations  ])ertaining  to  a  specified  rate  of  controlled  flow  of  the 
number  of  times  em])ty  space  in  excess  of  A^arious  values  was  needed. 
These  counts  were  expanded  by  ])roportion  to  obtain  the  number  of 
occurrences  had  the  records  been  a  hundred  years  in  length.  The  rela- 
tions disclosed  by  the  data  on  the  Sacramento.  ]\Iokelumne,  San  Joaquin 
and  San  Gabriel  rivers,  the  four  streams  selected  for  illustration,  are 
shown  on  Plates  X,  XI  and  XII,  "Reservoir  S])ace  Required  to  Control 
Floods."*  These  present  the  relations  established  from  the  data 
between  reservoir  s])ace  and  the  frequency  with  which  it  would  be 
surcharged  if  used  to  detain  excess  flood  flows. 

The  horizontal  scale  on  these  three  i)lates  shows  the  number  of  days 
in  a  hundred  years  that  reservoir  sjjace  in  excess  of  the  values  indicated 
on  the  vertical  scale  would  be  retiuired  in  a  reservoir  to  reduce  floods 
to  the  maximum  rate  of  flow  specified  on  the  curves.  For  convenience 
of  com])aris()n  between   the  twenty  streams  f<u"  which   these  computa- 

*  Water  Supply  Paper  Xo.  .").")1  of  the  I'nitetl  Stale.s  ( ieolofiical  Survey,  recently 
published,  i>lace.s  the  maximum  di.schar.^e  of  the  Mokelumne  River  at  Clements  at 
25,500  second  feet.  Tliis  is  obtained  by  appl>iiig  the  rating  curve  of  the  1911  flood 
to  the  KaKc  heights  of  1907.  The  crest  discharge  of  tin-  19(t7  flood  has  been  jiublished 
as  17.<Hi(i  seciiiid  feet  in  former  publicatif)ns  includinfr  Water  Supply  Paper  Xo.  299 
in  which  arc  pi'inted  the  daily  discharges  of  the  19(i7  flood.  The  lisures  contained  in 
Water  Supply  Paper  Xo.  2!i9  have  been  used  in  i)reparinK  this  volume.  Should  the 
dally  discharges  of  the  1907  flood  be  revised  by  appli<ation  of  the  1907  gage  heights 
to  the  I'Jll  rating  curve,  the  increase  in  their  values  would  be  so  substantial  as  to 
require  a  complete  revision  of  the  analyses  of  floods  on  the  Mokelumne  River  con- 
tained in  this  volume  in  order  to  make  tlie  analyses  harmonize  with  the  increased 
discharge    values. 


THE    COXTROL    OF    FLOODS    BY    RESERVOIRS. 


55 


PLATE   X. 


10.000 


^      1,000 


SACRAMENTO  RIVER  NEAR  RED  BLUFF 


<v    <D  ,a> 


<D    100 


^  oo 


CC  -o 


0.1. 


1 — 

pr-T 

] 

PTT5 

r— 

|-r- 

TTTT 

1    -TT 

=; 

=  = 

~""1 

— 

-- 

:i 

1        III 

Symb 

'lt^cSlS«^-f«' 

— 

1 

I 

30 
40 
50 
60 
^0        . 

24.900 
49,800 
74,700 

/Maximum  controlled  flow 

zz 

\\i\ 

10% 

= 

1 

;: 

"^.^ 

,,    . 

, 

99.600 
124,500 
149.400 
174  300 

^ 

-- 

30% 

=4+ 

:!i  ^ 

= 

s: 

'■■• 

"<, 

^ 

— 

i: 

^., 

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■f| 

SO  5; 

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Sr- 

% 

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s 

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pi 

k- 

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1 

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y 

^1 

\ 

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l\ 

i 

\ 





i 

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l._ 

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—  z 

^ 

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-i: 

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fl 

1 

1 

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0.1 


100 


1,000 


10.000 


100.000 


10,000 


SAN  GABRIEL  RIVER  NEAR  AZUSA 


1,000 


^  ^ 


c  r>J 


CD    «  100 


o 
S     10 


E 

:;; 

^ 

q 

= 

;  =  : 

= 

= 

=  =  : 

Symbr 

Maiimum 

to 

trolled  flow 

25->ear  flood  ~ 

>ccond  feet 

0 

5 
10 

i 

50 
60 

1,000 
1,900 
3.800 
5.800 
7.700 
9,600 
11,500 

= 

-J 

::: 

¥ 

III  1 

aximum  c 

xjntrollet 

lis 

w  !"* 

■t  ■ 

:  :  ti 

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f~jL.   ,:\ 

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30% 
771^ 

^^n;?*: 

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^^ 

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V'     ^»       Ni               3 

\m\ 

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1 

U 

).l  I  10  100  1,000  10,000  100,000 

Number  of  days  in  100  years  on  which  reservoir  space  is  exceeded 


Reservoir  Space  Required  to  Control  Floods 


CURVES   SHOW  NUMBER   OF  DAYS   IN  100  YEARS    ON  WHICH 

RESERVOIR   SPACE  GREATER  THAN    INDICATED  IS  NEEDED 

TO    CONTROL  FLOODS    TO    SPECIFIED    MAXIMUM    FLOW. 

M3)(lmum  controlled  flow  expressed  in  per  cent  of  Ireat-est  daily  rate  of  flow  of  a  once-in-25->e3r  flood 


56 


WATER    RESOURCES   OF    CALIFORNIA. 


PLATE  XI. 


MOKELUMNE  RIVER  NEAR  CLEMENTS 


100,000 


01  1  10  100  1.000  10,000  100,000 

Number  of  days  in  100  years  on  which  reservoir  space  is  exceeded 


Reservoir  Space  Required  to  Control  Floods 


CURVES    SHOW   NUMBER    OF  DAYS    IN   100   YEARS    ON  WHICH 

RESERVOIR   SPACE  GREATER   THAN    INDICATED   IS   NEEDED 

TO    CONTROL  FLOODS    TO    SPECIRED    MAXIMUM    FLOW 

Maximum  controlled  flow  expressed  m  percent  of  greatest  daily  rate  of  flow  of  a  once-in-2&;ye3r  flood 


THE    C;ONTKOL    OF   FLOODS   BY   RESERVOIRS. 


5T 


PLATE   XII, 


10,000 


,000 


SAN  JOAQUIN  RIVER  NEAR  FRIANT 


o 
o 

CO 

o" 


^ 


^ 


cc 


100 


=  =; 

::::■ 

="■ 

--: 

^4ti 

-:[-[-!  ili 

~ 

^ 

T 

-  -- 

■      " 

_- 

jMaximum  rontrolled  flow] 

'--' 

— 

-  Maximum  controllsd  flow 

-    : 



= 

2^>ear  flood 
20 
30 
40 
50 
60 
70 

7.100 
10,700 
14.200 
17,800 
21.100 
24,900 

/  .Rain  water  floodsGO^otolOX) 

2oiH/&j 

1 

^= 

-"i 

-= 

== 

:   :■ 

^ 

EE 



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■/— 

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1  1 

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70%2?-^^'"'^ 

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1 

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7     - 

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AT 

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1 

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1 

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=    : 

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-    - 

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1 

0.1 


100 


1,000 


10,000 


100.000 


10,000 


,000 


too  — 


— 

M 

— 

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-m 

! 

-- f 

= 

Ma 

xitnum  controlled  flow  1 

-  Max 

mum  controlled  flow 

I 1 

25-je3r  flood  ^^'""'•«' 

20              7,100 
30             10,700 
40             14,200 

/<^Snow  water  floods  (302  to  60 '/o) 

j^ 

/, 

r 

V     i       50       1      17,800 
<»     ■       60       I     21.400 

1    -t- 

Xv—/:  i::iii 

' '   1  '  1  i  i:| 

= 

-  ► 1 — ^-r~^-- 

\r,_[   .;  in-^ 

— 

\, 

I 

■ 

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4^t4o% 

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^*r 

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Tf 

"^S4 

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■•heoro 

t— ^" 

t  t^ 

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m^ 

I    1   1 

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\ 

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'N 

\ 

\ 

V- 

\ 

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-p 

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t~ 

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zz  : 

— -:  : 

—  • 

b^ 

— 

— »  — 







i 

* 

. 

0.1  I  10  100  1,000  10,000  100,000 

Number  of  days  in  lOOj/ears  on  which  reservoir  space  is  exceeded 


Reservoir  Space  Required  to  Control  Floods 


CURVES   SHOW   NUMBER  OF  DAYS   IN  100  VELARS    ON  WHICH 

RESERVOIR   SPACE  GREATER   THAN    INDICATED  IS  NEEDED 

TO    CONTROL  FLOODS    TO    SPECIFIED   MAXIMUM    FLOW. 

Maximum  controlled  flow  expressed  in  per  cent  of  greatest  dail_y  rate  of  flow  of  a  once-in-25-^e3r  flood 


58  WATER    RESOURCES    OF    CALIFORNIA. 

tions  were  made,  the  values  of  reservoir  space  were  expressed  in  per 
cent  of  the  greatest  daily  run-off  of  a  onee-in-25-year  flood.  The  rates 
of  flow  were  expressed  in  per  cent  of  the  jrreatest  daily  rate  of  flow  of  a 
'once-in-25-year  flood.  The  use  of  these  units  eliminates  the  dimensions 
of  the  drainage  area  and  permits  the  ready  com})ari,son  of  data  j^ertain- 
inp;  to  all  drainage  areas,  irresi)ective  of  their  size. 

The  curves  are  drawn  to  ex])ress  the  trend  of  the  plotted  data. 
Because  of  the  greater  mass  of  statistics  pertaining  to  the  smaller 
flows,  the  curves  relating  to  them  are  the  most  clearly  defined  by  the 
])lotted  points.  The  curves  for  the  larger  flows  are  drafted  by  com- 
])arison  with  those  for  the  smaller  ones  as  well  as  with  those  on  other 
streams,  while  at  the  same  time  conforming  to  the  i)lotted  points.  The 
data  on  some  streams  plot  closer  to  i-egular  curves  than  on  others.  In 
determining  the  general  sha{)e  of  tlie  curves  greater  weight  was  given 
to  tliese  data,  believing  that  the  greater  regularity  indicates  fewer 
departures  from  a  general  relation. 

It  may  be  observed  that  the  plotted  data  determining  the  i)arts  of  the 
curves  in  zones  of  greater  frequencies  on  the  right  of  the  graj^hs 
depart  less  from  the  smooth  curves  than  in  the  zones  of  smaller  fre- 
quencies on  the  left,  Avhere  the  points  are  determined  by  a  less  number 
of  floods.  The  point  in  each  series  farthest  to  the  left  is  computed 
from  the  largest  flood  during  the  period  of  record.  Although  it  has 
been  regarded  as  having  an  average  frequency  of  once  in  the  period  of 
record,  it  might  well  be  a  flood  of  some  other  frequency  that  happened 
to  occur  within  this  group  of  years,  since  the  relation  expressed  by  the 
curves  does  not  take  the  sequence  of  flood  sizes  into  account,  but  only 
the  average  interval  of  time  between  their  occurrence.  For  this  reason 
the  i)eriod  of  record  may  contain  single  floods  or  even  groups  of  floods 
that  have  actual  frequencies  different  from  those  indicated  by  their 
chance  occurrence  within  the  period  of  record.  Points  representing 
such  floods  on  the  graphs  would  be  expected  to  depart  from  smooth 
curves.  The  de]nirture  of  points  in  the  zones  of  smaller  frequencies 
toward  the  left  on  the  graphs  is  believed  to  be  from  this  cause. 
Therefore,  in  drafting  the  series  of  curves  to  re]iresent  the  average 
tendency  of  occurrence,  they  were  drafted  neither  to  average  the  points 
nor  to  pass  through  as  many  as  i)Ossible,  but  rather  they  were  drafted 
as  curves  of  regular  shape  taking  the  most  reasonable  position  rela- 
tive one  to  the  other  and  to  the  plotted  points  and  commen.surate  with 
the  indications  of  the  data  on  all  the  other  streams  .studied. 

Relations   established. 

The  curves  of  Plates  X,  XI,  and  XII  show  the  relation  between  reser- 
voir space  and  the  probable  frequency  with  which  specific  values  would 
be  surcharged  if  used  to  detain  excess  flood  flows.  They  yield  informa- 
tion upon  the  degree  of  certainty  with  which  floods  nuiy  be  controlled 
by  reservoirs  and  the  reserve  s])ace  needed  for  this  purpose.  Inter- 
.sections  of  the  curves  on  the  extreme  left  vertical,  indicate  the  rpserve 
s])ace  that  would  be  sufficient  to  detain  flows  in  excess  of  the  values 
specified  on  the  curves  for  all  except  one  day  of  flood  in  a  thousand 
years.  f)n  this  one  day,  the  indicated  reserve  sjiace  would  fill  and 
water  in  excess  of  the  specified  maximum  flow  would  have  to  be  dis- 
posed of.     This  day  may  be  one  of  either  small  or  large  flow  following 


THE    CONTROL    OF    FI^OODS    BY   RESERVOIRS. 


59 


close  upon  the  great  flood  that  filled  the  reserve  space  in  the  reservoir. 
The  only  information  yielded  by  the  analysis  is  that  the  reserve  space 
would  be  filled  to  overflowing.  The  amount  of  the  overflow  in  excess 
of  the  specified  maximum  discharge  might  take  any  value  greater  than 
zero  with  the  greatest  likelihood  of  its  being  among  the  smaller  values. 
Intersections  of  the  curves  with  verticals  other  than  the  one  on  the 


RESERVOIR  SPACE  REQUIRED  TO  CONTROL  FLOODS. 


Maximum 

controlled 

Reservoir  space  in  per  cent  of  greatest  dail> 

run-off 

fl 

ow 

of  once-in-25-year  flood 

In  per 

_ 

cent  of 

btream 

greatest 

Exceeded 

Exceeded 

Exceeded 

Exceeded 

Exceeded 

daily  rate 

In  second- 

one  day 

one  day 

one  day 

one  day 

one  day 

of  flow  of 

feet 

in  1000 

in  100 

in  .50 

in  25 

in  10 

once-in- 

years 

years 

years 

years 

years 

25-year 

flood 

Sacramento  River  near  Red  Bluff  . 

10 

24,900 

1,200 

1.190 

1,180 

1,165 

1,135 

20 

49,800 

620 

580 

563 

548 

519 

30 

74,700 

320 

282 

267 

249 

223 

40 

99,600 

198 

154 

140 

126 

104 

50 

124,500 

148 

105 

92 

78 

58 

60 

149,400 

121 

80 

66 

51 

32 

70 

174,.300 

102 

62 

48 

33 

16 

Mokelumne  River  near  Clements** 

Rain-Water  Floods. 

20 

*3,600 

*  1,000 

*960 

*940 

*920 

•900 

30 

5,. 300 

322 

278 

260 

237 

203 

40 

7,100 

240 

189 

172 

151 

119 

50 

8,900 

191 

141 

122 

102 

72 

60 

10.700 

153 

104 

87 

69 

42 

70 

12,500 

122 

76 

62 

46 

21 

Snow-Water  Floods. 

30 

5,300 

250      1        2.30      1        220 

211 

195 

40 

7,100 

50      1          40      1          36 

30 

23 

San  Joaquin  River  near  Friant   ... 

Raln-Water  Floods. 

20 

*7,100 

*I,320 

*1.310 

*1,300 

*1,280 

*1,260 

30 

10,700 

243 

209 

188 

168 

131 

40 

14,200 

188 

154 

138 

122 

94 

50 

17,800 

150 

120 

106 

90 

67 

60 

21,400 

123 

94 

81 

68 

48 

70 

24,900 

101 

74 

62 

50 

32 

Snow-Water  Floods. 

30 

10,700 

700 

678 

660 

645 

622 

40 

14,200 

270 

260 

250 

240 

222 

50 

17,800 

130 

117 

110 

102 

88 

60 

21,400 

60 

51 

46 

40 

30 

San  Gabriel  River  near  Azusa 

5 

1,000 

419 

390 

380 

370 

350 

10 

1,900 

344 

295 

277 

254 

225 

20 

3,800 

287 

225 

200 

170 

134 

30 

5,800 

243 

180 

1.54 

131 

93 

40 

7,700 

220 

150 

127 

102 

62 

50 

9,600 

197 

128 

104 

79 

37 

60 

11,500 

173 

107 

85 

59 

19 

70 

13,400 

153 

88 

67 

40 

5 

•Rain-water  and  snow-water  floods. 

**  Water  Supply  Paper  No.  551  of  the  United  States  Geological  Survey,  recently 
published,  places  the  maximum  discharge  of  the  Mokelumne  River  at  Clements  at 
25,500  second  feet.  This  is  obtained  by  applying  the  rating  curve  of  the  1911  flood 
to  the  gage  heights  of  1907.  The  crest  discharge  of  the  1907  flood  has  been  publi.shed 
as  17,000  second  feet  in  .former  publications  including  Water  Supply  Paper  No.  299 
in  which  are  printed  the  daily  discharges  of  the  1907  flood.  The  figures  contained  in 
Water  Supply  Paper  No.  299  have  been  used  in  preparing  this  volume.  Should  the 
daily  discharges  of  the  1907  flood  be  revi.sed  by  application  of  the  1907  gage  lieights 
to  the  1911  rating  curve,  the  increase  in  their  values  would  be  so  substantial  as  to 
require  a  complete  revision  of  the  analyses  of  floods  on  the  Mokelumne  River  con- 
tained in  this  volume  in  order  to  make  the  analyses  harmonize  with  the  increa.seci 
discharge    values. 


60  WATER    RESOURCES   OF    CALIFORNIA. 

extreme  left,  indicate  the  probable  frequency  with  which  smaller  values 
of  reservoir  space  would  fill  to  overflowing  while  regulating  to  the 
maximum  flows  specified  on  the  curves.  These  smaller  values  of  reser- 
voir space  are  indicated  on  the  vertical  scale  opposite  the  intersections 
while  the  frequencies  are  indicated  on  the  horizontal  scale  where  cut  by 
the  verticals  intersected. 

Values  determined. 

Tlie  values  of  reserve  reservoir  space  and  the  probable  frequencies 
witli  which  they  would  be  filled  to  overflowing  while  controlling  floods 
to  the  several  specified  rates  are  contained  in  the  foregoing  table  for  the 
four  illustrative  streams.  The  units  employed  are  relative  to  a  once-in- 
25-year  flood  and  are  identical  to  those  used  on  Plates  X,  XI  and  XII. 

It  may  be  observed  in  tlie  foregoing  table  that  the  relative  space 
required  to  control  floods  is  not  extremely  different  on  the  several 
streams  for  control  between  40  and  70  ])er  cent  of  the  onee-in-2o-year 
flood.  For  control  to  less  than  30  or  40  per  cent  of  the  once-in-25-year 
flood,  there  is  a  sharp  increase  in  the  reservoir  space  required  on  the 
three  northerly  streams.  On  the  San  Gabriel,  however,  this  sharp 
increase  occurs  for  control  to  less  than  10  or  20  per  cent  of  the  once-in- 
25-year  flood. 

On  all  four  streams,  for  rain-water  floods,  very  much  greater  space  is 
required  if  the  probability  of  control  is  raised  from  an  average  excep- 
tional behavior  of  one  day  in  10  years  to  one  day  in  1000  years.  For 
control  to  70  per  cent  of  the  once-in-25-year  flood,  the  space  increases 
from  5  to  32  per  cent  for  an  average  exceptional  behaA'ior  on  one  day 
in  10  years  to  101  to  153  per  cent  for  average  exceptional  behavior  on 
one  day  in  1000  years.  For  control  to  40  per  cent  of  the  onee-in-25-year 
flood  the  space  increases  from  62  to  119  per  cent  for  exceptional  behavior 
on  one  day  in  10  years  to  188  to  240  per  cent  for  exceptional  behavior  on 
one  day  in  1000  years.  These  values  increase  to  over  1000  per  cent 
for  control  to  less  than  10  or  20  per  cent  of  the  onee-in-25-year  flood 
on  the  three  northerly  streams  and  to  over  400  per  cent  for  control  to 
less  than  5  per  cent  of  the  once-in-25-year  flood  on  the  San  Gabriel. 

The  space  required  to  control  snoAv-water  floods  on  the  two  illustrative 
streams  on  Avhicli  they  occur  is  less  than  that  required  to  control  rain- 
water floods  except  for  reductions  to  less  than  50  per  cent  of  the  once- 
in-25-year  flood.  Larger  space  is  required  to  reduce  the  snow-water 
floods  to  these  smaller  rates  of  flow  than  to  correspondingly  reduce  the 
rain-water  floods.  In  general,  the  increase  in  space  for  gaining  greater 
probability  in  control  is  less  for  snow-water  floods  than  for  those  from 
rain. 

While  there  is  much  similarity  on  the  four  illustrative  streams  in  the 
relative  reservoir  space  refpiired  for  flood  control,  the  actual  space  in 
acre-feet  is  very  ditferent  due  to  the  gi-eat  variance  in  Uie  .si/e  of  the 
four  streams.     This  variance  in  size  is  shown  by  the  following  table : 

SIZE   OF   THE    FOUR    ILLUSTRATIVE   STREAMS. 

Drainage  area  Mean  seasonal  Maxinuim  flood 

in  square  miles  run-off  in  of  record — mean 

acre-feet  daily  flow  in 

River  second-fret 

Sacramento    9,258  9,029,000  2.S4.00O 

Mokelumne     632  898,000  16,700 

San     Joaquin 1.631  2,057,000  38,800 

San    Gabriel 214  147,000  22,300 


THE    CONTROL    OF   FLOODS   BY    RESERVOIRS. 


61 


The  actual  reservoir  space  in  acre-feet  required  to  control  floods,  cor- 
responding to  the  relative  values  heretofore  presented,  are  given  in  the 
following  table.  The  maximum  controlled  flows  are  expressed  in 
second-feet : 


RESERVOIR  SPACE  REQUIRED  TO  CONTROL  FLOODS. 


Maximum  controlled 
flow 

Reservoir  space  in  acre-feet 

In  per 

Stream 

cent  of 
greatest 

Exceeded 

Exceeded 

Exceeded 

Exceeded 

Exceeded 

daily  rate 

In  second- 

one  day 

one  day 

one  day 

one  day 

one  day 

of  flow  of 

feet 

in  1000 

in  100 

in  50 

in  25 

in  10" 

once-in- 

years 

years 

years 

years 

years 

25-year 

flood 

Sacramento  River  near  Red  Bluff. . 

10 

24,900 

5,926,000 

5,876,000 

5,827,000 

5,753,000 

5,605,000 

20 

49.800 

3,062.000 

2.864,000 

2.780,000 

2,706,000 

2..563.000 

30 

74,700 

1,580,000 

1,393,000 

1,318,000 

1,230.000 

1.101.000 

40 

99,600 

978,000 

760,000 

691,000 

622.000 

514.000 

50 

124,500 

731,000 

518.000  1     454.000 

385,000 

286,000 

60 

149,400 

597,000 

395.000  i     326.000 

252.000 

158,000 

70 

174,300 

504,000  i     306.000  1     237,000 

163.000 

79,000 

Mnkelumnc  River  near  Clements** 

Rain-Water  Floods. 

*20 

3,600 

353,000 

339,000 

332,000 

325,000 

318,000 

30 

5.300 

114,000 

98,000 

92,000 

84,000 

72,000 

40 

7,100 

85,000 

67,000 

61,000 

.53,000 

42,000 

50 

8,900 

67,000 

50,000 

43,000 

36.000 

25.000 

60 

10,700 

54,000 

37,000 

31,000 

24,000 

15,000 

70 

12,500 

43,000 

27,000 

22,000 

16,000 

7,000 

Snow-Water  Floods. 

30 

5,300 

88.000  i       81,000  1       78,000 

74,000 

69,000 

40 

7,100 

18,000  i        14,000  1       13,000 

11,000 

8,000 

San  Joarjuin  River  near  Friant.  .  . . 

Rain-Water  Floods. 

*20 

7,100 

932,000 

925,000 

918,000 

904,000 

890,000 

30 

10,700 

172,000 

148,000 

133.000 

119,000 

92,000 

40 

14,200 

133,000 

109,000 

97,000 

86,000 

60.000 

50 

17,800 

106,000 

85,000 

75,000 

04,000 

47.000 

60 

21.400 

87,000 

66,000 

57,000 

48,000 

31.000 

70 

24,900 

71,000 

52,000 

44,000 

35,000 

23,000 

Snow-Water  Floods. 

30 

10  700 

494,000 

479.000 

466,000 

455,000 

439,000 

40 

14,200 

191,000 

184.000 

177,000 

169,000 

1.57.000 

50 

17,800 

92,000 

83,000 

78.000 

72.000 

62.000 

San  Gabriel  River  near  Azusa 

GO 

21,400 

42,000 

36,000 

32,000 

28,000 

21,000 

5 

1,000 

160,000 

149,000 

145,000 

141.000 

133,000 

10 

1,900 

131,000 

112,000 

106,000 

97.000 

86,000 

20 

3,800 

109,000 

86,000 

76,000 

65,000 

51.000 

30 

5,800 

93,000 

69,000 

59,000 

50,000 

35,000 

40 

7,700 

84,000 

57,000 

48,000 

39,000 

24,000 

50 

9,600 

75,000 

49,000 

40,000 

30.000 

14,000 

60 

11,500 

66,000 

41.000 

32.000 

22,000 

7.000 

70 

13,400 

58,000 

34,000 

26,000 

15,000 

2.000 

*Rain-water  and  snow-water  floods. 

**  Water  Supply  I'aper  No.  551  of  the  United  States  Geological  Survey,  recently 
published,  place.s  the  niaxiniuni  discharg-e  of  the  Mokelumne  River  at  Clements  at 
25,500  second  feet.  This  is  obtained  by  applying  the  rating  curve  of  the  1911  flood 
to  the  gage  heights  of  1907.  The  crest  discharge  of  the  1907  flood  has  been  publislied 
as  17,000  second  feet  in  former  publications  including  "Water  Supply  Paper  No.  299 
in  which  are  printed  the  daily  di.scharge.s  of  the  1907  flood.  The  figures  contained  in 
Water  Supply  Paper  No.  299  have  been  used  in  preparing  this  volume.  Should  the 
daily  discharges  of  the  1907  flood  be  revised  by  application  of  the  19U7  gage  heights 
to  the  1911  rating  curve,  the  increase  in  their  values  would  be  so  substantial  as  to 
require  a  complete  revision  of  the  analy.ses  of  floods  on  the  Mokelumne  Uiver  con- 
tained in  this  volume  in  order  to  make  the  analvses  harmonize  with  tlie  increa.sed 
discharge   values. 


62  WATKR    RESOURCES    OF    CAIJKORMA. 

Variation    in   values  with  time  of  year  and   progressive    rainfall    index. 

The  reservoir  space  required  to  control  floods  deduced  by  the  fore- 
going anal3^sis  is  the  largest  that  may  be  needed  under  the  many  cir- 
cumstances of  flood  occurrence.  It  was  derived  from  a  discussion  of  all 
recorded  floods  regardless  of  the  time  of  year  or  the  value  of  i)rogressive 
rainfall  index  Avith  which  they  occurred.  The  reservoir  space  required 
to  control  floods  necessarily  will  vary  with  the  time  of  year  and  value  of 
the  progressive  rainfall  index  in  a  way  similar  to  the  size  of  floods  of 
which  it  is  a  function.  This  relation  of  reservoir  space  required  to  con- 
trol floods  to  the  time  of  year  and  value  of  progressive  rainfall  index 
parallels  so  closely  that  of  the  size  of  floods  which  is  fully  presented  in 
Chapter  III,  pages  29  to  50,  that  the  plates  setting  forth  the  correspond- 
ing analysis  in  respect  to  reservoir  s])ace  are  presented  without  further 
comment.  Plates  XIII  and  XIV,  "Relation  of  Time  of  Year  to  Need 
of  Reservoir  Space,"  are  constructed  in  an  identical  way  to  Plates  IV 
and  V,  "Relation  of  Time  of  Yeiir  to  Flood  Occurrence  (pp.  30  and 
82).  Likewise  Plates  XV,  XVI  and  XVII,  "Relation  of  Progressive 
Rainfall  Index  to  Need  of  Reservoir  Space,"  are  constructed  in  a  way 
identically  parallel  to  Plates  VII,  VIII  and  IX,  "Relation  of  Progres- 
sive Rainfall  Index  to  Flood  Occurrence"  (pp.  44,  45  and  46). 

The  limiting  dates  for  the  need  of  reservoir  space  to  control  floods 
on  the  four  illustrative  streams  are  found  to  vary  not  more  than  33  days 
from  the  corresponding  dates  of  flood  occurrence  (pp.  34  and  35)  while 
the  culminating  dates  are  not  more  than  11  days  apart.  Likewise  the 
limiting  values  of  i)rogressive  rainfall  index  with  which  reservoir  space 
is  needed  to  control  floods  do  not  differ  more  than  16  points  from  the 
corresi)onding  values  with  which  floods  occur  and  the  greatest  difference 
in  the  most  favorable  values  of  the  index  is  21  points.  A  complete 
tabulation  of  these  dates  and  values  of  i)rogressive  rainfall  index  follow. 
These  tables  are  parallel  in  every  respect  to  those  relating  to  flood 
occurrence  in  Chapter  111  (pp.  34,  35,  36,  48,  49  and  50)  except  that 
"need  of  reservoir  space  to  control  floods"  is  substituted  for  "flood 
occurrence." 


THE    CONTROL    OF    FLOODS    BY    RESERVOIRS. 


63 
PLATE  XIII. 


SACRAMENTO  RIVER 

NEAR 

RED 

BLUFF 

>mbo 

Maximum  controlled  flow  | 

AuA. 

%ofonce-in 
?5-jiear  flood 

Second  feet 

+ 

30 
40 
50 
60 
70 

74,100 
99,600 
I24„>)00 
149,400 
174.300 

.lillY 

June 

yMaximum  controlled  flow  to  obta 

n 

/ 

'  wtiich  reservoir  space  is  sometimes  nee 

d- 

-       / 

ed  subseo 

uent  to  indicflted  date 

May 

1 

_ 

_ 

--■wC- 

k_ 

■  'W^ 

,^ 

.\_ 

- .. 

^  ^  .. 

1 

April 

-\-  . 

_ 

, 

"  ~  ■ 

■  ■■  50% 

~  ' 

L  ..  ,_ 

1       ■  "•  ^ 

1 

V\ 

-  - 

- 

- ,, 

-  ■  i".:" 

*  *■ 

■■•>          -- 

., 

4- 

/ 

^- 

70  % 

.,"" 

!*■>  W 

t  l.+  l 

P 

Mar 

.   KJ^?    /-ilT] 

■^v 





^ 

...  -    P\X1\ 

.  J^^ 

_ 

-> 

4f 

Culminating  date     14 

Feb. 

Limiting  d^ 

tes  of 

— 

t^ 

^'-\ 

■'^ 

^ 

^ 

L?ft 

ot  need  oi 

reservoir  ] 

need  of  re 
space  to  con 

ervoir  _ 
rol  floods 

.        ^fi  ^      J     \ 

^ 

\ 

sV-' 

J^.V^i- 

space  locDnlrol  tloods.fl 

^.,^^^y 

'./S 

>  / 

TT 

1 

Jan. 

—A 

+           t 

'.''C       V 

X 

0    .  f' 

'      J^  '^'fl     "' 

\^ 

>' 

^" 

.>C 

' 

,               1 

Uec. 

/ 1 

.."^''^    > 

r 

hh 

_, 

--- 

'  ,'  -  ^  ' 

"I         _^ ' 

, 

^'f 

' 

1 

-■-  Where  data  ot  Iwo  or  r 

- — 

___ 

--•  ■ — 

^^ 

r 

1 

1 

-  ■  -  more  specified  sizes  of  |- 

Nov, 

—!         '" 

_L= 

...  50 -b 



5^-5 

,-',  .^ 



■ 

' 



y- 



r  ■  -  the  symbol  of  Ihe  larjest  (- 

^/^=^=*- 

*+  30% 

== 

— -  =  - 

— 

— 

+ 

L..|. 

shown.   A  numeral  - 
placed  at  Ihe  side  of  1 

Oct. 

~~ 

4+  ou^ 

'  ,  '   '1 

s 

which  reservoir  space  is  sometimes  nee 
ed  orjor  to  indicated  dates. 

d- 

symbols  of  neit  lower 

bept. 

order  reoresented  by  it. 



1     '  1  III II 

1 

1   '    II    1    III 

O.I 


100 


1,000 


10,000 


SAN 

GABRIEL  RIVER 

NEAR 

AZUSA 

1 

Sjmbo 

Maximum  coniroHed  flow  j 

Aug 

1 

%ofonce.in- 
?5yeor  flood 

jecond  feel 

I 

10 

^8 

40 
50 
60 
70 

3.800 
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13.400 

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t 

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ri 

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ed  subseauent  to  indicated  date 

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0.1  I 

Number  of  days  in 


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l^'ears  on  which  some  reservoir  space  is  needed 


I  Relation  of  Time  of  Year  to  Need  of  Reservoir  Space  | 

CURVES    SHOW   NUMBER    OF   DAYS    IN   100    YEARS    ON 

WHICH    SOME    RESERVOIR    SPACE    IS    NEEDED    PRIOR 

AND  SUBSEQUENT  TO  INDICATED  DATES  TO  CONTROL 

FLOODS    TO    SPECIFIED   MAXIMUM    FLOW 

Maximum  controlled  flow  expressed  in  percent  of  greatest  dail^  rate  of  flow  of  a  once-in-25->ear  flood 


64 


WATER   RESOURCES   OP    CALIFORNIA. 


PLATE    XIV 


MOKELUMNE  RIVER  NEAR  CLEMENTS 


1,000 

SAN  JOAQUIN  RIVER  NEAR  FRIANT 


10,000 


•laximum  controlled  flow  tor  snow  waterfloods  ro 
J  obtain  which  reservoir  space  is  sometimes  needed 
■  Subsequent  or  pnor  to  indicated  dates. 


0.1  I 

Number  of  days  in 


10  100  1,000  10,000 

l^ears  on  which  some  reservoir  space  is  needed 


Relation  of  Time  of  Year  to  Need  of  Reservoir  Space 


CURVES    SHOW   NUMBER    OF  DAYS    IN   100   YEARS    ON 

WHICH    SOME    RESERVOIR    SPACE    IS    NEEDED    PRIOR 

AND  SUBSEQUENT  TO  INDICATED  DATES  TO  CONTROL 

FLOODS    TO    SPECIFIED   MAXIMUM    FLOW 

Maximum  controlled  flow  expi^ssed  in  per  cent  of  greatest  dail^  rate  of  flow  of  a  once-in-25->ear  flood 


THE    CONTROL    OP   FLOODS    BY    RESERVOIRS. 


65 
PLATE  XV. 


300 


z=  200  i\- 


v>    100 


SACRAMENTO  RIVER  NEAR  RED  BLUFF 


— 

~ 

""T 

nr 

>mbol 

q 

%ofonce,n- 

Second  feet 

74,700 
99,600 
124,500 
149,400 
174  300 

-- 

o             40 
V            50 
«            60 
t            70 

- 

V 

space  is  sometimes  needed  with  values  of  pro- 



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r  the  need  of  nsservoir  I 

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f 

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f 

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1 

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Maxjmurr 

controlled  flow  to  obtain  wtiich  reservoir 

~ 

L-- 

1  _    IS  placed  at  the  sidr  of 
such  symbols   wh.ch  in 

space  IS  sometimes  needed  with  values  ot  pro- 
gressive rainfall  index  less  than  inrjir^tfid 

dicates  the  number  of  i 

5 

mbols  of  neit  lower    1 

''i  1  Mill     1   iTirlTi'i     1  i 

onJer 

repne 

se 

nted  by 

,t.| 

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,000 


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GABRIEL  RIVER 

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AZUSA 

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10 
20 
30 
40 
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. ',  f'  ' ', ' 

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- 

" 

/ 

space  is  sometimes  needed  with  values  of  pro- 

/- 

300 

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^cl  indicarea. 



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space 

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symbols -of  next  lower  [1 

1     1    1 

n 

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1       1 

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inT 

dll 

index 

Ifib^i 

JUi 

UJi 

IV'-II 

0.1  I  10  100  1.000  10,000 

Number  of  days  in  100  jears  on  which  some  reservoir  space  is  needed 


Relation  of  Progressive  Rainfall  Index  to  Need  of  Reservoir  Space 


CURVES    SHOW    NUMBER    OF     DAYS    IN    100    YEARS    ON    WHICH 

SOME   RESERVOIR    SPACE    IS    NEEDED     TO     CONTROL    FLOODS 

TO  SPECIFIED  MAXIMUM  FLOW  WITH  VALUES   OF  PROGRESSIVE 

RAINFALL  INDEX    GREATER    AND    LESS    THAN    INDICATED. 

Maximum  controlled  flow  expressed  in  per  cent  of  greatest  dail>  rate  of  flow  of  a  once-in-25-_year  flood 


5—52411 


66 


WATER   RESOURCES   OK    OALIFORiNIA. 


PLATE    XVI. 


400 


300 


■-  200 


•QO 


Q-    100 


MOKELUMNE  RIVER  NEAR  CLEMENTS 


■ 

TSturfkDd 

0      ^8 

•            70 

5,300 
1.100 
8.900 
10.700 
12,500 

iMaximum  controlled  flow  for  rain 

/floods  to  obtain  wtiicti  reservoir  sp 

sometimes  needed  witti  values  of  p 

ive  rainfall  index  greater  than  inc 

:::     / 

■■    / 

icated  ' 

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— ■ 

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su*  symbols  wt)icti  in- 

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symbol 

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ace  IS 

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L 

1 

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1  1 

0.1 


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1,000 


10.000 


400 


300 


200 


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a.   100 


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s 

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25-,MrfloM 

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30 
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5.300 
7.100 

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placed  at  the  Side  erf  1 

such  symbols  which  in- J 

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Maximum  controlled  flow  for  snow 
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ive  rainfall  index  less  tha 

ri  ino 

Tr 

1    1   1  Mill          1      1 

III 

100 


1,000 


10.000 


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Relation  of  Progressive  Rainfall  Index  to  Need  of  Reservoir  Swvce 


CURVES    SHOW    NUMBER     OF     DAYS     IN    100     YEARS    ON    WHICH 

SOME  RESERVOIR    SPACE    IS    NEEDED     TO    CONTROL    FLOODS 

TO  SPECIFIED   MAXIMUM  FLOW  WITH  VALUES    OF  PROGRESSIVE 

RAINFALL  INDEX    GREATER   AND   LESS    THAN   INDICATED. 


Maximum  controlled  flow  expressed  in  per  cent  of  greatest  daily  rate  of  flow  of  a  once-ln-25-ycar  flood. 


THE    CONTROL    OP   FLOODS   BY   RESERVOIRS. 


()7 
PLATE  XVn. 


o 


400 

SAN 

JOAQUIN  RIVER 

NEAR 

FRIANT 

Symtwt 

Majimum  umtrolled  flow   1 

%ofonce-in- 
25-«3rni»d 

Second  feet 

30 

10.100 
14,200 
n,800 
21,400 
24,900 

60 
70 

300 

1 

1  1  1  1 1 

Where  data  of  two  or 

more  specified  sizes  of 

flow  are  coincident.onl^ 

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J  of  pro^'^essive 

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I 

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placed  at  the  side  of  f] 

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200 

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400 


300 


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^bo 

Maximum  controlled  flow  | 

%ofonce-in- 
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\ 

30 
40 
50 
60 

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17.800 
21,400 

V 

- 

nore  specified  sizes  of 

1 

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le  symbol  of  the  lan^ 

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d 

icates  the  number  of 

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s 

ymbols  of  next  lower 

m  m  rnntrnlipH  fin     f 

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Number  of  days  in  lOO^ears  on  which  some  reservoir 


1,000  10,000 

space  is  needed 


I  Relation  of  Progressive  Rainfall  Index  to  Need  of  Reservoir  Space 


CURVES    SHOW    NUMBER     OF     DAYS    IN    100    YEARS    ON    WHICH 

SOME  RESERVOIR    SPACE  IS   NEEDED    TO    CONTROL    FLOODS 

TO  SPEOnED  MAXIMUM  FLOW  WITH  VALUES   OF  PROGRESSIVE 

RAINFALL  INDEX    GREATER   AND  LESS   THAN  INDICATED. 

Maximum  controlled  flow  expressed  in  per  cent  of  |reatest  dail^  rate  of  flow  of  a  once-in- 25-year  flood 


68 


WATER    RESOURCES   OF    CALIFORNIA. 


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WATER   RESOURCES   OP    CALIFORNIA. 


CULMINATING  DATE  FOR  NEED  OF  RESERVOIR  SPACE  TO  CONTROL 

FLOODS. 


Maximum 
controlled  flow 

Date 

In  per  cent  of 

greatest  daily  rate 

of  flow  of 

once-in-25-year 

flood 

Sacramento 

River 

near  Red 

Bluff 

Mokelumne  River 
near  Clements 

San  Joaquin  River 
near  Friant 

San  Gabriel 

River 
near  Azusa 

Rain-water 
floods 

Snow-water 
floods 

Rain-water 
floods 

Snow-water 
floods 

10 

Feb.    7 

20 

Feb.    7 

30 
40 
50 

Feb.    4 
Feb.    4 
Feb.    4 
Feb.    4 
Feb.    4 

Feb.  22 
Feb.  18 
Feb.  15 
Feb.  14 
Feb.  12 

May  28 
June    7 

Jan.   18 
Jan.   19 
Jan.  20 
Jan.  21 
Jan.  22 

May  26 
June    4 
June    5 
June    6 

Feb.    7 
Feb.    7 
Feb.    4 

60 

Feb.    4 

70 

Feb.    4 

SACRAMENTO   RIVER. 

LIMITING    VALUES    OF    PROGRESSIVE    RAINFALL   INDEX*   BETWEEN 
WHICH  RESERVOIR  SPACE  IS  NEEDED  TO  CONTROL  FLOODS. 


Maximum 

controlled 

Minimum  index  values 

Maximum  index  values 

flow  near 

Red  Bluff 

Frequency  with  which  some  reservoir  space  is 

Frequency  with  which  some  reservoir  space  is 

In  per 

needed,  with  progressive  rainfall  index 

needed,  with  progressive  rainfall  index 

cent  of 

less  than  values  tabulated 

greater  than  values  tabulated 

greatest 

In 

second- 

daily  rate 
of  flow  of 

foct 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

25-ycar 
flood 

in  1000 

in  100 

in  50 

in  25 

in  10 

in  1000 

in  100 

in  50 

in  25 

in  10 

years 

years 

years 

years 

years 

years 

years 

years 

years 

years 

30 

74,700 

42 

47 

49 

52 

58 

212 

206 

202 

197 

188 

40 

99,600 

46 

61 

54 

58 

65 

205 

199 

194 

188 

178 

50 

124,500 

50 

56 

59 

64 

72 

199 

191 

186 

179 

164 

60 

140,400 

54 

60 

64 

70 

81 

193 

183 

177 

167 

148 

70 

174,300 

57 

64 

68 

76 

95 

188 

176 

168 

155 

127 

*At  Red  Bluff  rainfallstation. 


THE    CONTROL    OF   FLOODS   BY   RESERVOIRS. 


71 


MOKELUMNE  RIVER. 

LIMITING   VALUES    OF  PROGRESSIVE    RAINFALL    INDEX*    BETWEEN 
WHICH  RESERVOIR  SPACE  IS  NEEDED  TO  CONTROL  FLOODS. 


Maximum 
flow  near 

controlled 
Clements 

Minimum  index  values 

Maximum  index  values 

Frequency  with  which  some  reservoir  space  is 

needed,  with  progressive  rainfall  index 

less  than  values  tabulated 

Frequency  with  which  some  reservoir 

needed,  with  progressive  rainfall  i 

greater  than  values  tabulatec 

In  per 
cent  of 
greatest 

In 

second- 
feet 

space  IS 
adex 

daily  rate 

of  flow  of 

once-in- 

25-year 

flood 

One  day 
in  1000 

One  day 
in  100 

One  day 
in  50 

One  day 
in  25 

One  day 
in  10 

One  day 
in  1000 

One  day 
in  100 

One  day 
in  50 

One  day 

in  25 

One  day 
in  10 

years 

years 

years 

years 

years 

years 

years 

years 

years 

years 

Rain-Water  Floods. 

30 
40 
50 
60 
70 

5,300 
7,100 
8,900 
10,700 
12,500 

50 
56 
62 
68 
74 

55 
61 
67 
74 
81 

58 
64 
71 
78 
86 

62 
69 
77 
86 
97 

70 
78 
88 
103 

240 
226 
212 
200 
188 

228 
213 
198 
185 
172 

222 
207 
191 
177 
163 

215 
199 
183 
168 
151 

204 
186 
169 
150 

S 

new-Water  Floods. 

30 
40 

5,300 
7,100 

67 
83 

68 
84 

69 
85 

70 
86 

72           164 
89           156 

163 
154 

162 
153 

161 
151 

159 
149 

*At  Electra  rainfallstation. 


SAN  JOAQUIN  RIVER. 

LIMITING  VALUES   OF    PROGRESSIVE     RAINFALL    INDEX*    BETWEEN 
WHICH  RESERVOIR  SPACE  IS  NEEDED  TO  CONTROL  FLOODS. 


I 


Maximum 
flow  nea 

controlled 
r  Friant 

Minimum  index  values 

Maximum  index  values 

Frequency  with  which  some  reservoir  space  is 

needed,  with  progressive  rainfall  index 

less  than  values  tabulated 

Frequency  with  which  some 

needed,  with  progressive 
greater  than  values 

reservoir 
rainfall 
tabulatec 

In  per 

cent  of 

greatest 

daily  rate 

In 

space  IB 
ndex 

j 

of  flow  of 

once-in- 

25-year 

flood 

second- 
feet 

One  day 
in  1000 

One  day 
in  100 

One  day 
in  50 

One  day 
in  25 

One  day 
in  10 

One  day 
in  1000 

One  day 
in  100 

One  day 
in  50 

One  day 
in  25 

One  day 
in  10 

years 

years 

years 

years 

years 

years 

years 

years 

years 

years 

Rain-Water  FloodSj 

30 
40 
50 
60 
70 

10,700 
14,200 
17,800 
21,400 
24,900 

45 
53 
60 
66 
71 

47 
55 
62 
69 
74 

49 
57 
65 
71 

77 

52 
60 
68 
76 
83 

59 
70 
79 
89 
101 

190 
186 
182 
179 
176 

185 
181 
177 
173 
169 

183 
179 
174 
170 
164 

179 
175 
170 
164 
157 

173 
167 
160 
151 
140 

Snow-Water  Floods. 

30 
40 
50 

60 

10,700 
14,200 
17,800 
21,400 

60 
69 

77 
84 

62 
71 
80 
88 

64 
73 
82 
91 

65 
74 
84 
94 

68 
77 
88 
101 

150 
143 
138 
134 

148 
140 
134 
129 

147 
139 
133 
127 

146 
137 
131 
125 

144 
135 
128 
119 

*At  Fresno  rainfallstation. 


72 


WATER    RESOURCES    OF    CALIFORNIA. 


SAN  GABRIEL  RIVER. 

LIMITING  VALUES   OF   PROGRESSIVE    RAINFALL    INDEX*    BETWEEN 
WHICH  RESERVOIR  SPACE   IS  NEEDED  TO  CONTROL  FLOODS. 


Maximum 

controlled 

Minimum  index  values 

Maximum  index  values 

flow  nca 

r  Azusa 

Frequency  with  which  some  reservoir 

space  is 

Fre(iiicncy  with  which  some  reservoir 

space  18 

In  per 

needed,  with  progressive  rainfall  index 

needed,  with  progressive  rainfall  index 

cent  of 

less  than  values  tabulated 

greater  than  values  tabulated 

greatest 

In 

daily  rate 

of  flow  of 

second- 
feet 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

One  day 

once-in- 

in  1000 

in  100 

in  50 

in  25 

in  10 

in  1000 

in  100 

in  50 

in  25 

in  10 

25-year 
flood 

years 

years 

years 

years 

years 

years 

years 

years 

years 

years 

10 

1,900 

27 

30 

32 

35 

40 

294 

282 

277 

270 

257 

20 

3.800 

35 

39 

41 

45 

51 

279 

264 

256 

245 

226 

30 

5,800 

42 

47 

49 

53 

61 

265 

248 

238 

226 

203 

40 

7.700 

48 

54 

57 

63 

78 

252 

233 

222 

207 

181 

50 

9,600 

54 

59 

66 

77 

102 

241 

219 

206 

189 

158 

60 

11,500 

58 

66 

76 

90 

127 

230 

205 

191 

173 

133 

70 

13,400 

63 

73 

86 

106 

220 

193 

178 

156 

*At  Claremont  rainfall  station. 


MOST  FAVORABLE  VALUES  OF  PROGRESSIVE  RAINFALL  INDEX  FOR 
NEED  OF  RESERVOIR  SPACE  TO  CONTROL  FLOODS. 


Maximum 
controlled  flow 

Sacramento 

Hivor 

near  lied 

Bluff 

Mokelumnc  River 
near  Clements 

San  .loacpiin  River 
near  Friant 

San  Gabriel 

[n  per  cent  of 

greatest  daily  rate 

(if  How  of 

once-in-25-ycar 

flood 

Haiii-water 
floods 

iSnuw-water 
floods 

liaiii-wat(  r 
floods 

SiiDW-waler 
floods 

Itiver 
near  Azusa 

10 

122 

20 

117 

30 
40 
50 

110 
110 
110 
111 
110 

130 
129 
128 
128 
125 

120 
120 

122 
122 
122 
122 
122 

no 
no 
no 
no 

121 

126 
118 

60 

130 

70 

1X1 

THE    CONTROL    OF    FLOODS    BY   RESERVOIRS.  73 


CHAPTER  V. 


THE  RESERVOIR  OPERATING  DIAGRAM  FOR  CONTROLLING 

FLOODS. 

Principles  of  operating  reservoirs  for  controlling  floods. 

The  use  of  reservoirs  for  flood  control  in  California,  being  of  c«m- 
paratively  recent  date,  has  not  been  standardized  by  the  engineering 
profession.  The  practice  varies.  In  general,  reservoirs  now  in  use  for 
flood  control  have  allotted  either  the  entire  or  a  specific  part  of  their 
capacity  for  this  purpose  alone.  The  usual  method  of  operation  is  to 
hold  this  entire  space  empty  at  all  times  except  as  it  may  be  tempo- 
rarily filled  while  detaining  excessive  flood  flows  and  the  water  that 
accumulates  while  thus  controlling  floods  is  released  as  soon  as  the 
streams  subside  in  order  that  this  .space  may  be  empty  for  the  control 
of  the  run-off  of  subsequent  storms.  Any  water  that  is  retained  in 
storage  is  held  upon  the  prediction  of  the  reservoir  operators  that  the 
space  occupied  by  it  will  not  be  needed  again  that  season  for  controlling 
floods. 

The  prediction  that  floods  will  not  occur  again  in  any  season  involves 
an  estimate  of  future  weather  conditions,  the  most  uncertain  of  all 
events.  When  water  is  stored  in  flood  control  reservoirs  on  such  an 
estimate,  an  error  results  in  failure  in  control  of  subsequent  floods 
because  the  reservoir  space  needed  to  detain  excessive  rates  of  flow 
would  already  be  filled  with  water  held  from  the  first  storm.  Failure 
in  the  control  of  floods  means  the  loss  of  property  and  sometimes  of 
human  life.  Were  this  danger  not  real,  flood  control  reservoirs  would 
not  be  built.  For  matters  of  such  importance,  it  would  seem  unsafe  to 
rely  upon  the  judgment  of  operators  in  the  most  uncertain  of  predic- 
tions, especially  since  the  decisions  of  gravest  moment  must  be  made 
during  the  stress  of  large  floods.  The  risk  of  an  error  in  judgment 
under  these  circumstances  is  too  great  for  attaining  surety  in  protec- 
tion. For  this  reason  the  use  of  flood  control  reservoirs  for  conserva- 
tion purposes  generally  has  not  been  looked  upon  with  favor. 

For  a  like  reason,  many  engineers  propose  the  exclusion  of  manually 
operated  gates  on  the  outlets  of  flood  control  reservoirs.  Contention 
is  made  that  the  risk  is  great  in  relying  upon  human  activity  of  any 
kind  during  critical  periods ;  rather,  they  would  have  the  reservoir 
discharge  its  water  and  empty  automatically  through  ports  in  the  dams 
with  fixed  openings.  This  view,  however,  would  seem  to  be  somewhat 
extreme,  for  it  is  now  common  practice  to  place  manually  operated 
gates  in  the  spillways  of  reservoirs.  These  are  closed  toward  the  end 
of  the  run-off  season  in  order  to  utilize  the  top  layers  of  the  reservoir 
for  storing  water.  They  are  opened  again  after  the  summer's  draft 
has  lowered  the  reservoir  level,  but  before  the  next  season's  rains. 
Should  the  attendants  fail  to  open  these  gates,  the  capacity  of  the  spill- 
way would  be  destroyed  and  a  fair-sized  flood  would  overtop  the  dam. 
[n  spite  of  this  danger,  reliance  is  placed  on  the  manual  operation  of 
these  gates  to  clear  the  spillway  prior  to  the  occurrence  of  a  flood. 


74  WATER   RESOURCES   OP   CALIFORNIA. 

The  manual  operation  of  control  mechanism  is  customary  in  many 
other  lines  of  endeavor  -where  the  safety  of  life  and  property  is  involved, 
especially  in  our  transportation  system.  Custom  relies  upon  hand- 
controlled  signals,  valves  and  steering  apparatus  for  the  safety  of  life 
and  property  in  all  modes  of  transportation.  Dispatchers,  tower  men, 
engineers  of  railroads,  auto-bus  drivers,  and  captains  of  ocean-going 
vessels,  in  the  faithful  and  exact  performance  of  their  duty,  hold  within 
their  hands  the  safety  of  millions  of  passengers  and  va.st  wealth.  These 
men  are  required  to  operate  apparatus  under  guiding  rules.  Judgment, 
other  than  that  necessary  for  applying  the  guiding  rules,  is  not  needed. 
Because  of  the  many  successful  years  of  the  operation  of  our  trans- 
portation systems  on  both  land  and  water,  it  would  seem  that  the  man- 
ual .  operation  of  apparatus  under  guiding  rules  is  quite  safe.  By 
analogy,  therefore,  it  would  not  seem  necessary  for  safety  to  exclude 
the  use  of  manually  operated  gates  on  the  outlets  of  flood  control  reser- 
voirs, provided  that  guiding  rules,  definite  and  enforcible,  be  laid  down 
for  their  opening  and  closing. 

Without  gates  controlled  by  hand  on  the  outlets  of  flood  control 
reservoirs,  a  coordinated  use  of  their  space  for  both  flood  control  and 
eon.servation  is  impossible.  Gates  that  may  be  closed  when  desired 
are  necessary  in  order  that  flood  control  reservoirs  may  store  water  for 
any  length  of  time.  Therefore,  the  safe  use  of  the  same  reservoir  space 
for  both  flood  control  and  conservation  is  contingent  upon  working 
out  definite  guiding  rules  for  opening  and  closing  the  outlet  gates  that 
do  not  employ  judgment  in  their  execution  and  that  can  be  enforced. 

Rules  for  opening  and  closing  reservoir  outlet  gates  that  will  control 
floods  with  certainty  may  be  worked  out  easily  enough  if  no  attempt 
is  made  to  avoid  interference  with  the  conservation  values  of  the  reser- 
voirs. To  produce  rules,  however,  that  will  hold  sufficient  reservoir 
space  empty  during  the  flood  season  to  assure  the  successful  control  of 
floods  while  at  the  same  time  releasing  this  space  as  the  season  pro- 
gresses so  that  it  ma.y  fill  with  water  before  the  end  of  the  run-off  season, 
is  a  complex  undertaking.  It  has  been  the  purpose  of  these  investiga- 
tions to  develop  the  principles  upon  which  such  rules  might  be  scien- 
tifically constructed  and,  by  way  of  illustration,  to  construct  several 
rules,  test  tlieir  accuracy  and  determine  tlieir  effect  on  conservation. 
These  principles  have  been  developed  in  the  foregoing  chapters.  The 
construction  of  the  rules,  the  test  of  their  accuracy  and  the  determina- 
tion of  their  effect  on  conservation  occupy  this  and  the  concluding 
chapters. 

The  reservoir  operating  diagram. 

it  lias  been  pointed  out  in  the  preceding  chapters,  that  the  same 
amount  of  reservoir  space  is  not  needed  for  controlling  floods  at  all 
times  during  a  season  nor  in  all  seasons.  The  amount  of  space  needed 
under  the  many  circumstances  of  time  of  year  and  type  of  season  is 
iletermined  by  the  analysis  of  the  need  of  reservoir  space  for  controlling 
floods  described  in  the  previous  pages.  In  general,  the  amount  of  space 
needed  for  detaining  excessive  flood  flows  so  that  only  limited  amounts 
pass  the  reservoir  increases  from  zero  in  the  early  fall  to  a  maximum 
in  midwinter  and  tlien,  as  the  season  progresses,  decreases  to  zero  in 
the  forepart  of  summer.     It  also  fluctuates  with  the  normalcy  of  the 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  75 

season's  precipitation.  In  general,  summarizing  the  deductions  of  the 
first  four  chapters,  when  the  seasonal  precipitation  to  date  is  less  than 
half  or  more  than  double  normal,  large  floods  do  not  occur.  Under 
these  conditions,  reservoir  space  is  not  needed  for  flood  control  regard- 
less of  the  time  of  year.  It  is  needed  in  the  largest  volume  when  the 
precipitation  to  date  is  between  normal  and  50  per  cent  above.  The 
largest  floods  occur  under  these  circumstances  and  the  maximum  reser- 
voir space  is  then  required  for  controlling  floods.  Space  in  amounts 
intermediate  between  zero  and  the  maximum  is  necessary  when  the 
seasonal  precipitation  to  date  is  between  50  and  100  or  between  150 
and  200  per  cent  normal.  The  exact  value  of  these  requirements 
varies  with  each  stream  and  the  degree  of  control  desired. 

The  amount  of  reservoir  space  required  under  the  many  variant  cir- 
cumstances of  time  of  year,  type  of  season,  and  degree  of  desired  control 
may  be  specifically  derived  through  analyses  similar  to  the  ones  in  the 
preceding  chapters.  Having  determined  these  amounts,  rules  may  be 
laid  down  that  will  release  the  space  required  for  flood  control  as  soon 
as  its  need  for  that  purpose  has  passed.  This  space  may  then  fill  for  con- 
servation. The  dependability  of  such  rules  for  controlling  floods  rests 
upon  the  selection  of  adequate  amounts  of  space  to  be  held  empty 
during  the  flood  season.  Their  value  to  conservation  rests  upon  the 
immediate  release  of  this  space  for  filling  as  soon  as  its  need  for  flood 
control  has  passed.  Thus,  the  determination  of  the  amount  of  space 
that  should  be  held  empty  during  the  flood  season  and  of  the  time 
that  all  or  part  of  it  may  be  released  safely  for  filling  is  the  foundation 
for  formulating  rules  for  the  combined  use  of  the  same  reservoir  space 
for  both  flood  control  and  conservation. 

The  rules,  as  devised  by  this  investigation,  are  expressed  in  the  form 
of  graphic  diagrams  which  show  the  amount  of  reservoir  space  that,  for 
the  circumstance  existing  on  any  current  day,  should  be  empty  in  order 
to  assure  the  degree  of  flood  control  desired.  The  reservoir  outlet  gates 
would  be  opened  or  closed  daily  as  may  be  necessary  to  provide  within 
24  hours  the  required  empty  space  indicated  on  the  diagram.  The 
gates  would  be  opened  when  this  space  is  less  than  indicated  and  the 
discharge  through  the  outlets  is  less  than  the  desired  maximum  con- 
trolled flow.  The  gates  would  be  closed  whenever  the  empty  space  in 
the  reservoir  is  greater  than  indicated  on  the  diagram.  All  inflow  to 
the  reservoir  would  then  enter  storage  except  as  water  may  be  with- 
drawn for  some  useful  purpose. 

These  graphic  rules  are  called  "Reservoir  Operating  Diagrams  for 
Controlling  Floods."  Each  diagram  applies  to  a  particular  stream 
and  to  a  particular  degree  of  control.  The  degree  of  control  is 
expressed  by  the  maximum  controlled  flow  desired  at  some  point  of 
measurement  and  the  probability  that  this  will  not  be  exceeded.  This 
probability  is  measured  in  the  analyses  herein  described  by  the  number 
of  days  in  an  average  hundred  years  on  which  greater  flows  may  occur. 
The  greater  the  assurance  of  perfect  control,  the  larger  is  the  amount  of 
reservoir  space  required  and  the  longer  is  the  period  during  which  it 
should  be  held  empty.  Practical  values  in  accord  with  the  danger  to 
life  and  property  must  be  selected  for  design  purposes  in  each  instance. 
For  sparsely  settled  rural  lands,  it  is  thought  that  adequate  protection 
would  be  had  if  the  desired  maximum  controlled  flow  were  exceeded  on 


76  WATEi:    KESOUKC'ES    OF    CALIFORNIA. 


PLATE    XVI II. 


■) 

100 

200 

300 

400 

50 

20 

July 

^    10 

1 

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— 

20 

June 

10 

Reservoir  outlet  gates  to  be  opened  or  closed  daily  as  may  be 
necessary  to  provide  wahin  24  hours  the  unoccupied  space  indi- 
cated on  diagram  for  the  current  day  and  value  of  progressive 
tainfall  index.  Release  from  reservoir  limiled  in  rate  in  order  that, 
in  combinin|  with  run-off  downslream  from  reservoir  the  maximum 
controlled Tlow  will  not  be  exceeded  at  point  of  measurement. 
Curved  lines  on  diagram  are  marked  with  values  of  the  pro- 
gressive rainfall  index.  Black  lines  are  used  for  values  of 
iTO  or  less  and  red  lines  for  greater  values. 

20 

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100  200  300  400 

Reservoir  space  in  thousands  of  acre  feet 


500 


Reservoir  Operating  Diagram 
FOR  Controlling  Floods  on  Sacramento  River 


MAXIMUM  CONTROLLED  FLOW  NEAR  RED  BLUFF-125,000  SEC.  FT. 

CURVES  SHOW   SPACE  NEEDED  AT  VARYING   TIMES  OF  YEAR  AND  VALUES 
OF  PROGRESSIVE  RAINFALL  INDEX  TO  ABSORB  EXCESSIVE  FLOOD  FLOWS. 


i2411 — rage   76 


THE    CONTROL    OP    Ff.OODS    I?Y    REl^ERVOIRS.  77 

an  average  not  oftener  tlian  one  day  in  25  years,  while  for  very  thickly 
populated  territory,  it  probably  should  not  be  exceeded  oftener  than 
one  day  in  a  thousand  years  or  more. 

After  selecting  the  degree  of  control  desired,  a  reservoir  operating 
diagram  for  controlling  floods  may  be  constructed  for  any  stream  from 
the  analyses  of  its  flow  measurements.  This  diagram  would  apply  only 
to  reservoirs  having  drainage  areas  between  them  and  the  point  of 
measurement  that  do  not  produce  floods  greater  than  the  selected 
maximum  controlled  flow.  In  releasing  water  from  reservoirs  located 
upstream  from  the  point  of  measurement,  the  amount  would  be  gov- 
erned by  the  flow  at  the  point  of  measurement.  The  release  from  the 
reservoir  would  be  limited  to  an  amount  that,  combined  with  the  natural 
run-off  from  the  drainage  area  downstream,  would  not  exceed  the 
desired  controlled  flow  at  the  point  of  measurement. 

The  analyses  of  stream  flow  data  required  for  the  construction  of  a 
reservoir  operating  diagram  are  identical  to  those  described  in  Chapter 
IV.  The  analyses  there  described  of  the  stream  flow  data  on  the  Sacra- 
mento, Mokelumne,  San  Joaquin  and  San  Gabriel  rivers  furnish  infor- 
mation for  the  construction  of  reservoir  operating  diagrams  for  any 
desired  degree  of  flood  control  on  these  four  streams.  The  construction, 
from  this  information,  of  a  diagram  for  one  selected  degree  of  control 
on  each  of  the  four  streams  is  described  in  the  following  pages  of 
this  chapter. 

For  convenience  in  working  with  these  diagrams,  the  use  of  the  name 
"progressive  rainfall  index"  that  represents  the  normalcy  of  seasonal 
precipitation  in  the  analyses  of  Chapters  III  and  IV  has  been  con- 
tinued. It  is  the  ratio  of  the  precipitation  from  July  1st  up  to  any 
current  day  in  a  season  to  the  normal  precipitation  for  the  same  period. 
Its  value  changes  daily  as  the  season  progresses. 

In  using  the  diagrams,  it  is  necessary  to  maintain  a  rain  gage  in 
order  to  obtain  the  current  value  of  the  progressive  rainfall  index. 
This  gage  should  be  read  and  the  value  of  the  progressive  rainfall 
index  computed  on  each  day.  The  diagram  should  be  entered  with 
this  value  and  the  amount  of  space  read-off  that  should  be  empty  at 
the  end  of  the  current  day.  The  outlet  gates  should  then  be  regulated 
to  obtain  this  empty  space  so  far  as  may  be  done  without  causing  a 
flow  at  the  point  of  measurement  greater  than  the  desired  maximum. 
If  the  reservoir  outlet  gates  were  so  regulated  daily,  by  reason  of  the 
method  of  constructing  the  diagram,  the  reservoir  would  not  be  expected 
to  fill  to  overflowing  except  at  the  average  intervals  contemplated  in 
the  selection  of  the  degree  of  probable  control.  At  these  average  inter- 
vals, the  reservoir  would  be  expected  to  overflow  while  the  maximum 
controlled  flow  is  passing  the  point  of  measurement.  Thus,  the  maxi- 
mum controlled  flow  below  the  reservoir  may  be  exceeded  by  the  amount 
of  this  overflow  at  the  average  intervals  selected  in  the  construction  of 
the  diagram.  The  amount  of  the  overflow  might  be  anything  larger 
than  zero  with  the  greatest  likelihood  of  its  being  among  the  smaller 
values. 

Reservoir  operating  diagram  for  controlling  floods  on   Sacramento   River. 

Plate  XVIII,  "Reservoir  Operating  Diagram  for  Controlling  Floods 
on  Sacramento  River,"  presents  in  graphic  form  the  rule  for  operating 


78  WATER   RESOURCES   OF    CALIFORNIA. 

a  reservoir  on  the  main  Sacramento  River  in  order  to  limit  the  flow 
in  the  channel  near  Red  Bluff  to  125,000  second-feet.  It  indicates  the 
space  in  the  reservoir  that  should  be  empty  in  order  to  detain  run-off 
in  excess  of  this  desired  regulated  flow  for  all  conditions  of  previous 
rainfall  on  every  day  of  the  season.  The  amount  of  space  that  should 
be  empty  changes  with  the  time  of  year  and  the  normalcy  of  the  season's 
precipitation  as  shown  by  the  value  of  the  progressive  rainfall  index. 
A  maximum  of  454,000  acre-feet  is  required  to  be  empty  in  the  fore 
part  of  February  if  the  precipitation  up  to  that  time  is  10  per  cent 
above  normal.  On  preceding  and  subsequent  days  the  space  required 
becomes  less  until  prior  to  November  21st  and  subsequent  to  April  8th, 
no  space  is  needed  at  all.  The  required  space  also  becomes  less  for 
seasonal  precipitation  to  date  either  larger  or  smaller  than  10  per  cent 
above  normal  and  reaches  zero  for  precipitation  greater  than  186 
per  cent  or  less  than  59  per  cent  normal. 

Had  there  been  a  reservoir  in  existence  and  operated  in  accord  with 
til  is  diagram  through  the  thirty  years  of  stream  flow  record  on  the 
Sacramento  River,  the  flow  at  Red  Bluff  would  not  have  exceeded 
125,000  second-feet  at  any  time.  Even  the  greatest  flood  of  record 
on  February  3,  1909,  which  reached  a  crest  discharge  of  278.000  second- 
feet,  would  have  been  limited  to  a  flow  of  125,000  .second  feet,  153.000 
second-feet  less  than  the  actual  occurrence.  Although  controlling  floods 
to  this  discharge,  the  diagram  holds  space  in  the  reservoir  empty  no 
longer  than  necessary.  Thus,  the  nde  of  reservoir  operation  laid  down 
by  this  diagram  interferes  a.s  little  as  possilile  with  the  use  of  the  reser- 
voir for  conservation. 

The  diagram  applies  to  any  reservoir  of  more  tlian  454.000*  acre- 
feet  capacity  that  might  be  constructed  on  the  main  Sacramento  River 
between  the  Red  Bluff'  gaging  station  and  the  Kennett  reservoir  site 
near  the  confluence  with  the  Pit  River.  It  does  not  apply  to  reservoirs 
further  upstream  than  Kennett  because  it  is  estimated  that  a  flood  as 
large  as  125,000  second-feet  may  originate  on  the  drainage  area  down- 
stream from  Kennett  but  tributary  to  the  Red  Bluff  gaging  station. 

The  values  of  the  progressive  rainfall  index  used  in  the  construction 
of  the  diagram  were  computed  from  the  rainfall  records  of  the  United 
States  Weather  Bureau  at  Red  Bluff". t  These  values  are  marked  on 
the  curved  lines  of  the  diagram.  Black  lines  are  used  for  values  of 
no  or  less  and  red  lines  for  greater  values.  The  intersections  of  the 
curved  lines  with  the  horizontal  date  lines  indicate  on  the  lower  scale 
the  amount  of  empty  space  needed  at  any  time.  The  diagram  assumes 
that  the  reservoir  outlet  gates  will  be  opened  or  closed  daily  as  may  be 
necessary  to  provide  as  nearly  as  possible  within  24  hours  Avithout 
causing  the  desired  regulated  flow  to  be  exceeded,  the  empty  space 
indicated  on  the  diagram  for  tbe  current  day  and  value  of  progressive 
rainfall  index.  If  the  reservoir  were  located  upstream  from  Red  Bluff", 
the  release  through  the  outlet  gates  would  be  limited  to  amounts  that 
would  not  exceed  125,000  .second-feet  after  combining  with  the  run-off 
from  the  drainage  area  between  the  reservoir  and  Red  Bluff. 


•  The  reservoir  space  nooded  for  flood  control  in  addition  to  454,000  acre-feet  is 
that  which  would  furnish  the  minimum  operating  head  on  the  reservoir  outlets  to  dis- 
charge 125,000  second-feet. 

t  Red  Bluff  is  one  of  the  principal  stations  in  precipitation  division  B  of  which  most 
of  the  flood  producing  arta  of  the  Siicramento  Drainage  Basin  is  part.  See  Chap.  II, 
Bui.  5,  "Flow  in  California  Streams,"  issued  by  the  Division  of  Engineering  and  Irri- 
gation, State  Department  of  Public  Works. 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  79 

The  degree  of  control  selected  for  construction  of  the  Sacramento 
River  diagram  contemplates  that  the  desired  regulated  flow  may  be 
exceeded  on  an  average  of  one  day  in  fifty  years.  This  was  used  in 
taking  values  off  the  charts  of  Chapter  IV  for  constructing  the  diagram. 
The  maximum  reservoir  space  required  under  the  most  severe  circum- 
stances is  taken  from  Plate  X,  p.  55.  In  the  upper  figure  on  this  plate, 
reading  the  50  per  cent  curve  (124,500  second-feet),  it  is  found  that 
reservoir  space  in  the  amount  of  92  per  cent  of  the  greatest  daily  run-oif 
of  a  once-in-25-year  flood  (454,000  acre-feet)  is  sufficient,  on  the  aver- 
age, to  control  floods  to  125,000  second-feet  maximum  flow  at  Red  Bluff 
on  all  but  one  day  in  fifty  years.  The  time  at  which  this  maximum 
space  is  required  is  taken  from  the  upper  figure  of  Plate  XIII,  p.  63. 
The  intersection  of  the  full  and  dotted-line  curves  labeled  50  per  cent 
(124,500  second-feet)  determines  that  the  culminating  date  of  need  of 
reservoir  space  to  control  floods  is  February  4th.  This  date  and  the 
maximum  reservoir  space  needed  locate  on  the  diagram  the  apex  of  the 
outside  curve,  the  one  of  largest  values  of  reservoir  space. 

The  two  arms  of  the  outside  curve  are  fixed  in  position  by  their  inter- 
sections with  the  vertical  line  on  the  left  representing  zero  reservoir 
space.  Their  intersections  with  this  vertical  read  on  the  time  scale  are 
at  the  days  before  and  after  which  reservoir  space  is  not  needed  to 
control  floods.  These  dates  are  determined  on  the  upper  figure  of 
Plate  XIII,  p.  63,  by  the  intersection  of  the  50  per  cent  curves  (124,500 
second-feet)  with  the  vertical  representing  two  days  in  100  years  on 
which  some  reservoir  space  is  required  to  conti'ol  floods.  The  full-line 
curve  intersects  at  November  21st,  the  date  before  which  reservoir  space 
is  not  needed.  The  dotted-line  curve  intersects  at  April  8th,  the  day 
after  which  reservoir  space  is  not  needed.  These  two  dates,  plotted  on 
the  operating  diagram  on  the  line  of  zero  reservoir  space,  fix  the  position 
of  the  arms  of  the  outside  curve.  With  the  apex  and  the  position  of 
the  two  arms  fixed,  the  shape  of  the  curve  was  estimated  from  a  study 
of  the  data  on  twenty  major  streams  in  California  and  by  the  trial 
construction  of  diagrams.  The  shape  given  is  the  one  that  seems  to  fit 
the  data  best. 

This  curve,  outermost  of  all  others  on  the  diagram,  expresses  the 
largest  values  of  reservoir  space  that  are  required  at  any  time.  The 
amount  of  space  indicated  by  it  should  be  held  empty  wdien  the  condi- 
tions of  previous  rainfall  are  most  favorable  for  the  need  of  reservoir 
space  to  control  floods.  The  value  of  the  progressive  rainfall  index 
most  favorable  for  the  need  of  reservoir  space  is  taken  from  the  upper 
figure  of  Plate  XV,  p.  65.  Here  the  dotted  and  full-line  curves  repre- 
se'iiting  control  to  50  per  cent  of  a  once-in-25-year  flood  (124,500  second- 
feet)  intersect  at  a  value  of  110  read  on  the  scale  of  progressive  rainfall 
index.  This  is  the  most  favorable  value  for  need  of  reservoir  space  to 
control  floods  and  hence  is  the  value  of  the  progressive  rainfall  index 
that  applies  to  the  outside  curve  of  the  operating  diagram. 

The  interior  curves  that  indicate  the  empty  space  required  with 
values  of  the  progressive  rainfall  index  either  greater  or  less  than 
the  one  calling  for  the  largest  amount  of  empty  reservoir  space  are 
drawn  of  a  shape  similar  to  the  outside  curve.  There  is  one  black 
curve  for  each  increment  of  five  in  the  values  of  the  progressive  rainfall 
index  less  than  110,  and  one  reel  curve  for  each  increment  of  ten  in 


80  WATER   RESOURCES    OF    CALIFORNIA. 


PLATE  XIX. 


0                             20                            40                             60                            80                            100 

20 

July 

10 

Sv 

20 

June 

^ 

\\ 

<    m  120 

H 

\ 

i<i^ 

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85' 

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20 

150^ 

f      140/ 

V. 

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r 

20 
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^ 

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*si. 

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'^ly-^ 

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"^ 

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^ 

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^-^ 

^* 

~.^ 

20 

Mar. 

10 

V 

N, 

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^ 

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^ 

> 

w 

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"~\ 

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>i 

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n; 

Sw. 

% 

s  ■ 

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vN 

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s« 

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\50 

N 

,90 

\ 

100   "< 

s     110^ 

o^e^ao^ 

> 

^ 

\, 

\ 

\ 

\ 

\      ^ 

N^ 

■> 

<C\> 

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\ 

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1 

\ 

k 

\ 

\ 

\ 

20- 

Feb. 

10 

9, 

\      . 

\  , 

i 

j 

i 

1 

/    , 

/ 

/// 



/ 

/ 

'      I 

- 

t-1^^ 

/ 

/// 

22 

2  210 

2I(/ 

2oq 

190  / 

180     > 

170      /1 60     150  140 

20 

Jan 

10 

/ 

/ 

"7 

// 

/ 

// 

/ 

/\ 

'  / 

/ 

/ 

/ 

^// 

/ 

i 

// 

/ 

/ 

/ 

A 

v^ 

y 

/    Za 

/l 

y 

/ 

/ 

/ 

^ 

y 

/ 

'J 

/ 

// 

y 

V 

/ 

iy 

■^, 

/  f 

f 

/ 

y 

^y 

^^^ 

^y 

*^ 

// 

20 

Dec. 

10 

J 

'   / 

^/ 

^ 

y 

-^ 

l^ 

J^ 

^ 

/ 

/ 

/. 

' 

\y 

^ 

^ 

^^ 

^ 

If 

/ 

/ 

t 

y 

/ 

^ 

y' 

^ 

^ 

^ 

d 

^^ 

Progressive  rainfall  index/ 

/ 

y^ 

/ 

^ 

^ 

^ 

fe 

<^ 

aSP 

^ 

/ 

S« 

^ 

^ 

^ 

>^^ 

;> 

0^ 

^ 

20 

Nov. 

10 

^ 

/^ 

'^ 

^ 

^ 

Reservoir  outlet  gates  to  be  opened  or  closed  daily  as  ma>  b 
necessary  to  provide  within  24  hours  the  unoccupieo  space  indi 
cated  on  diagram  for  the  current  day  and  value  of  progressive  rai 
fall  index.  Release  from  reservoir  limited  in  rate  in  order  that 
in  combining  with  runoff  downstream   from  reservoir,  the  maximun 
controlled  now  vvill  not  be  exceeded  at  point  of  measurement 
Curved  lines  on  diagram  are  marked  with  values  of  the  pro^re 
ive  rainfall  index.    Black  lines  are  used  for  values  of  130  or 

e 
1 

55- 

20 

Oct. 

10 

less  for  rain-water  and  120  or  less  for  snow-water  floods.     1 

0                             20                            40                             60                           80 

Reservoir  space  in  thousands  of  acre  feet 

IC 

0 

Reservoir  Operating  Diagram 
FOR  Controlling  Floods  on  Mokelumne  River 

MAXIMUM  CONTROLLED  FLOW  NEAR  CLEMENTS 

FOR 

RAIN  WATER  FLOODS    -    5,300  SEC.  FT. 
SNOW  WATER  FLOODS  -  7J00  SEC.  FT. 

CURVES  SHOW  SPACE  NEEDED  AT  VARYING  TIMES  OF  YEAR  AND  VALUES 
OF  PROGRESSIVE   RAINFALL  INDEX    TO  ABSORB  EXCESSIVE    FLOOD  FLOV\/S. 

52411— Page    80 


TTTE    OON'PROT^   OF    l''I,OOnS    liV    RKSKRVOIHS.  81 

the  values  of  the  progressive  rainfall  index  greater  than  110.  The 
curve  of  smallest  index  value  is  65  and  largest  180.  Both  are  close  to 
the  zero  ordinate  of  reservoir  space  on  the  diagram.  The  index  values 
coinciding  with  the  zero  ordinate  of  reservoir  space  are  59  and  186. 
These  are  the  limiting  values  hetween  which  reservoir  space  is  required 
to  control  floods.  No  space  is  needed  when  the  index  is  either  smaller 
or  larger,  respectively.  These  values  are  derived  from  Plate  XV,  p.  65. 
In  the  upper  figure  on  this  plate,  the  two  50  jier  cent  curves  (124,500 
second-feet)  intersect  the  vertical  representing  two  days  in  100  years 
that  values  will  be  exceeded,  at  59  and  186  on  the  vertical  scale  of 
progressive  rainfall  index.  The  intersection  of  the  full-line  curve 
shows  that,  for  values  of  the  pi-ogressive  rainfall  index  less  than  59, 
reservoir  space  is  not  reciuired  oftener  than  two  days  in  100  years. 
Similarly,  the  intersection  of  the  dotted-line  curve  sliows  that  reservoir 
space  is  not  required  to  control  floods  except  for  two  days  in  100  years 
when  the  progressive  rainfall  index  exceeds  186. 

The  positions  of  the  apices  of  the  several  interior  curves  on  the 
diagram  are  interpolated  between  the  outside  curve  of  maximum  reser- 
voir space  and  zero  on  the  reservoir  space  scale  along  the  line  repre- 
senting February  4th,  the  culminating  date  for  need  of  reservoir  space 
in  controlling  floods.  They  are  not  arranged  with  uniform  intervals 
between  them,  but  rather  take  positions  having  increasingly  smaller 
intervals  as  the  maximum  reservoir  space  is  approached.  The  arms  of 
the  interior  curves  are  drawn  of  the  same  general  shape  as  the  outside 
curve  and  are  interpolated  in  position  with  increasingly  smaller  inter- 
vals between  them  toward  the  latter  part  of  the  flood  season.  While 
normally  the  arms  toward  the  fore  part  of  the  flood  season  would  take 
similar  positions,  since  at  this  time  of  the  year  the  index  values  fluctuate 
rapidly  and  are  not  well  established,  they  are  all  passed  through 
November  21st  on  the  zero  reservoir  space  line,  the  opening  date  of  the 
flood  season.  This  manner  of  fixing  the  positions  of  the  apices  and  arms 
of  the  interior  curves  was  found  to  fit  the  data  best  after  construction 
of  many  trial  and  supplementary  diagrams  on  this  and  other  streams 
and  for  other  degrees  of  flood  control. 

Reservoir  operating  diagram  for  controlling  floods  on   Mokelumne  River. 

The  rule  for  operating  a  reservoir  to  control  floods  on  the  Mokelumne 
River  is  expressed  on  Plate  XIX,  "Reservoir  Operating  Diagram  for 
(Jontrolling  Floods  on  Mokelumne  River."  As  on  the  one  for  the 
Sacramento  River,  the  Mokelumne  River  diagram  indicates  the  space 
in  a  reservoir  that  should  be  empty  on  each  day  of  the  season  for  all 
conditions  of  previous  precipitation  in  order  to  detain  discharges  in 
excess  of  a  certain  desired  controlled  flow.  The  Mokelumne  River  dia- 
gram would  limit  the  flow  near  (Mements,*  the  point  of  measurement  on 
the  Mokelumne  River,  to  a  maximum  of  5)300  second-feet  for  rain-water 
floods  and  7100  second-feet  for  snow-water  floods.  The  diagram  applies 
to  any  reservoir  within  a  distance  of  about  80  miles  upstream  from 
Clements.  The  reservoir  would  need  to  have  a  capacity  greater  than 
92,000*  acre-feet,  the  maximum  space  required.  The  Mokelumne  dia- 
gram, like  that  for  the  Sacramento,  assunu>s  that  the  reservoir  outlet 

*  The  reservoir   space   needed   for   flood   control   in   addition   to    92,000   acre-feet   is 
that  which  would  furnish  the  minimum  operating  head  on  the  reservoir  outlets  to  dis- 
charge  5300   second-feet. 
G— 52411 


82  WATER   RESOURCES   OP    CALIFORNIA. 

gates  will  be  opened  or  closed  daily  as  niaj-  be  necessary  to  provide  as 
nearly  as  possible  Avithin  24  hours  without  causing  a  tlow  at  Clements 
greater  than  desired,  the  empty  space  indicated  on  the  diagram  for  the 
current  day  and  value  of  progressive  rainfall  index. 

The  chief  distinction  betAveen  this  diagram  and  the  one  for  the  Sacra- 
mento River  is  that  it  provides  for  controlling  snow-water  floods  in  the 
early  summer.  These  do  not  occur  on  the  Sacramento  but  are  a  part 
of  the  normal  regime  of  tiie  ]\Iokelumne  River.  The  Mokelumne  dia- 
gram provides  for  limiting  their  maximum  rate  of  discharge  to  7100 
second-feet,  1800  second-foet  more  than  tlie  maximum  controlled  flow 
for  rain-water  floods.  It  is  estimated  that  these  two  controlled  flows 
would  be  about  equivalent  one  to  the  other  in  the  lower  channel  of  the 
river  because  the  snow-water  flow  will  be  reduced  by  summer  diver- 
sions for  irrigation  while  the  natural  run-off  downstream  from  the 
point  of  measurement  will  contribute  some  to  the  regulated  rain-water 
floods. 

The  greatest  rain-water  flood  contained  in  the  twenty-one  years  of 
stream-flow^  record  at  Clements  occurred  on  January  30,  1911.  The 
crest  discharge  was  20,600*  second-feet,  15,300  second-feet  larger  than 
the  controlled  floAv  to  which  rain-water  floods  would  be  limited  by 
reservoir  operation  in  accordance  with  the  diagram.  The  mean  daily 
flow  on  January  30,  1911,  was  16,700  second-feet.  The  largest  snow- 
Avater  flood  appears  in  the  record  on  June  12,  1906,  Avitli  a  discharge 
of  8740  seeoud-feet.  Tliis  is  only  1640  second-feet  larger  than  the  con- 
trolled snow-water  floAv  that  would  result  from  use  of  the  diagram. 
Since  snow-water  floods  do  not  attain  as  great  a  rate  of  floAv  as  those 
from  rain  water,  large  reductions  are  not  necessary  in  order  to  con- 
fine them  to  a  channel  of  reasonable  size.  For  this  reason  the  reser- 
voir space  required  for  the  control  of  snow-water  floods  on  the  Mokel- 
umne River  is  much  less  than  for  the  control  of  rain-Avater  floods.  The 
greatest  space  required  in  order  to  limit  snoAV-Avater  floods  to  7100 
second-feet  is  13,000  acre-feet.  A  maximum  of  92,000  acre-feet  is 
required  to  limit  rain-Avater  floods  to  5300  second-feet. 

On  the  Mokelumne  diagram  during  the  period  of  rain-Avater  floods, 
the  greatest  space  is  held  empty  Avhen  the  progressive  rainfall  index 
has  a  value  of  130  and  during  the  period  of  snoAV-Avater  floods,  Avhen 
it  has  a  A'alue  of  120.  The  curves  in  ))lack  indicate  the  space  to  be  held 
empty  for  index  values  less  than  130  and  120.  respectively.  Avhile  the 
curves  in  red  indicate  the  space  to  be  lichl  empty  for  greater  index 
values.  The  extreme  values  between  Avliieli  any  iv.servoir  space  is 
needed  at  all  are  58  and  222  for  rain-Avater  floods  and  So  and  153  for 
snoAv-Avater  floods.  These  differ  someAvhat  from  the  corresponding 
values  on  the  Sacramento  River  diagram.  Similarly,  the  limiting  dates 
of  the  flood  season  are  slightly  different.  Unlike  the  Sacramento  dia- 
gram, hoAvevei',  that  for  tlie  ^lokelumne  liohls  a  small  amount  of  .space 

•  Water  Supply  Paper  No.  551  of  the  United  States  GeolOK>cal  Survey,  recently 
published,  places  the  maximum  discharge  of  the  Mokelumne  River  at  Clements  at 
25,500  socond-ffot.  This  is  obtained  by  applying  the  rating  curve  of  the  1911  flood 
to  the  page  heights  of  1907.  The  crest  rti.scharge  of  the  1907  flood  has  been  published 
as  17,000  second-feet  in  former  publications  including  AA'ator  Supply  Paper  No.  299 
in  which  are  printed  the  daily  di.«5charges  of  the  1907  tlood.  The  figures  contained  in 
AVat<-r  Supply  Paper  No.  299  have  been  used  in  preparing  this  volume.  Sliould  the 
daily  discharges  of  the  1907  flood  be  revised  by  application  of  the  1907  gage  heights 
to  the  1911  rating  curve,  the  increase  in  their  values  would  be  so  substantial  as  to 
require  a  complete  revision  of  the  analyses  of  floods  on  the  Mokelumne  River  con- 
tained in  this  volume  in  order  to  make  them  harmonize. 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  83 

empty  between  May  lltli  and  July  otli  for  the  control  of  snow-water 
floods  that  do  not  occur  on  the  Sacramento  River. 

The  diagram  for  controlling  floods  on  the  Mokelumne  River  is  con- 
structed in  a  way  identical  to  that  previously  described  for  the  one  on 
the  Sacramento  River;  the  same  probability  of  average  exceptional 
behavior  of  one  day  in  50  years  was  selected,  and  the  values  are  taken  in 
exactly  the  same  way  from  the  analyses  of  Chapter  IV  which  were 
carried  out  in  parallel  for  the  four  illustrative  streams.  The  values  of 
the  progressive  rainfall  index  used  in  the  Mokelumne  River  analyses 
were  computed  from  the  records  of  the  United  States  Weather  Bureau 
station  at  Electra.*  This  is  the  station  at  which  the  rainfall  index 
should  be  determined  in  applj'ing  the  diagram. 

The  maximum  reservoir  space  required  on  the  Mokelumne  diagram 
under  the  most  severe  circumstances  is  taken  from  Plate  XI,  p.  56. 
Reading  the  30  per  cent  (5300  second-feet)  curve  for  rain-water  floods 
and  the  40  per  cent  (7100  second-feet)  curve  for  snow-water  floods,  the 
reservoir  space  required  for  flood  control  except  probably  on  an  average 
of  two  days  in  100  years  is  260  per  cent  of  the  greatest  daily  run-off 
of  a  once-in-25-year  flood  (92,000  acre-feet)  for  the  control  of  rain- 
water floods  and  36  per  cent  (13,000  acre-feet)  for  the  control  of  snow- 
water floods. 

The  culminating  date  of  the  two  flood  seasons,  at  which  time  ilie 
maximum  empty  space  is  needed,  is  determined  from  the  upper  figure 
of  Plate  XIV,  p.  64.  Here,  on  the  part  pertaining  to  rain-water  floods, 
the  intersection  of  the  dotted  and  full-line  curves  labeled  30  per  cent 
(5300  second-feet)  shows  the  culminating  date  of  the  season  to  be  Feb- 
ruary 22d;  on  the  part  pertaining  to  snow-water  floods,  the  intersection 
of  tiie  dotted  and  full-line  curves  labeled  40  per  cent  (7100  second- 
feet)  shows  the  culminating  date  of  the  snow-water  flood  season  to  be 
June  7th.  These  two  dates  on  which  maximum  empty  space  is  needed 
fix  the  position  on  the  time  scale  of  the  apices  of  the  two  sets  of  curves 
of  the  reservoir  operating  diagram. 

The  positions  of  the  arms  of  the  outside  curves  are  fixed  by  the 
limiting  dates  of  the  flood  season.  These  dates  are  taken  from  the 
upper  figure  of  Plate  XIV,  p.  64.  On  the  part  of  this  figure  per- 
taining to  rain-water  floods,  the  intersections  of  the  two  30  per  cent 
(5300  second-feet)  curves  with  the  vertical  representing  two  days  in 
100  years  on  w^hich  some  reservoir  space  is  needed  to  control  floods, 
give  November  17th  and  April  21st  as  the  limiting  dates  of  the  flood 
season.  Similarly,  on  the  part  pertaining  to  snow-water  floods,  the  two 
40  per  cent  (7100  second-feet)  curves  intersecting  on  the  same  vertical 
indicate  the  limiting  dates  for  this  season  to  be  May  11th  and  July  5th. 
The  arms  of  the  outside  curves  on  the  reservoir  operating  diagram  pass 
through  these  dates  on  the  line  of  zero  reservoir  space.  The  .shape  of 
the  curves  was  determined  by  the  preparation  of  supplementary  and 
trial  diagrams  in  the  same  way  as  for  the  Sacramento  River  diagram. 

The  value  of  progressive  rainfall  index  Avith  whicli  this  maximum 
reservoir  space  is  needed  is  taken  from  Plate  XVI,  p.  66.  Here  the 
intersections  of  the  full  and  dotted-line  curves  labeled   30  per  cent 

♦  Electra  is  a  cooperative  station  of  the  United  States  Weatlier  Bureau  and  one 
of  tlie  principal  stations  in  precipitation  division  K  of  which  the  Mokelumne  drainage 
basin  is  part.  See  Chapter  II,  Bui.  5,  "Flow  in  California  Streams,"  issued  by  the 
Division  of  Engineerinjj  and  Irrigation,  State  Department  of  Public  Works. 


84  WATER    RESOURCES    OF    CAUFORXIA. 


PLATE  XX. 


c 

40 

80 

12 

iO 

160 

20 

20 

July 

^   10 

-=  = 

= 

^~~- 

;r~ 

»._^ 

20 

June 

10 

L-^ 

..^ 

^^ 

-..^^ 

---. 



■»N^ 

■^ 

"•-«, 

•^ 

75 

80 

90 

-^ 

100 

■t«^ 

" 

\ 

\ 

\ 

\ 

> 

73 --1' 

9 

; 

7 

) 

i 

1 

20 

May 

^  10 

^ 

^ 

130 

^ 

'    1^ 

--^ 

^ 

— 

^^^ 

'-' 

. 

«••"* 

i 

'^^i^ 

s= 

M 

^ 

-^ 

20 

April 

^      10 

t>. 

-^ 

20 

Mar. 

10 

?N 

^^ 

5-~^ 

?=5 

t^ 

^ 

Pr 

ogressive  rainfall  index^ 

"~- 

^ 

'--^ 

-:^ 

r^ 

s^ 

!5^ 

1 

^-^ 

[^  "■ 

^-> 

^ 

>x; 

l*^ 

^* 

1 

^ 

^- 

"^ 

^ 

-^ 

^^ 

1  1 

20 

Feb. 

10 

■'"V 

**^^ 

^    "^ 

On.  'i^ 

s^V,  ^ 

j 

^^ 

^ 

"V, 

^^ 

:^^ 

1 

"v 

N 

"^ 

^ 

\ 

\ 

\.  ^ 

s[Ni^ 

1 

S, 

\ 

N 

N 

N 

^V 

j 

\ 

^ 

\ 

\ 

k^ 

1 

\ 

60 

\ 

70 

\, 

80 

mi2o' 

20, 

Jan    ' 

10 

50 

V 

\ 

\ 

\ 

\ 

\N^ 

\ 

1 

\ 

\ 

\ 

\ 

9  I 

) 

/ 

/ 

/ 

/ 

/ 

/    \ 

/ 

t:i7 

80 

y 

170 

/ 

IfiO   /       1S(/ 

\M^ 

1 

20 

Dec 

10 

?,^ 

1 

/ 

/ 

/ 

/    y/ 

/ 

/ 

// 

y 

y 

^^ 

/ 

^ 

> 

y 

'^ 

^/ 

^ 

^ 

/ 

^. 

^^^ 

20 

Nov. 

10 

— 

/ 

^ 

/> 

^ 

^ 

>^ 

^',<: 

^y* 

^^ 

^i^ 

Reservoir  outlet  gates  to  be  opened  or  closed  daily  as  may  be 
necessary  to  provide  within  24  hours  the  unoccupied  space  indi- 
cated on  diagram  for  the  current  day  and  value  of  progressive  rain- 
fall index.  Release  from  reservoir  limited  in  rate  in  order  that, 
in  combining  with  run-off  downstream  from  reservoir,  the  maximum 
controlled  flow  will  not  be  exceeded  at  point  of  measurement. 
Curved  lines  on  diagram  are  marked  with  values  ofthe  progres'' 
ive  rainfall  index.  Black  lines  are  used  for  values  of  120  or 
less  for  rain-water  and  110   or  less  for  snow-water  floods 
Red  lines  are  used  for  greater  values  in  each  instance. 

/ 

"^ 

^ 

>-' 

■< 

s*^ 

-^ 

^ 

^ 

^ 

20 

Oct. 

10 

^ 

>* 

1 

1        1        1        1        1        1        1        1        1        1        1        1        1 

40 


80 


120 


160 


200 


Reservoir  space  in  thousands  of  acre  feet 


Reservoir  Operating  Diagram 
FOR  Controlling  Floods  on  San  Joaquin  River 


MAXIMUM  CONTROLLED  FLOW  NEAR  FRIANT 

FOR 

RAIN  WATER  FLOODS    -  10,700  SEC.  FT. 
SNOW  WATER  FLOODS  -14,200  SEC.  FT. 

CURVES  SHOW   SPACE  NEEDED  AT  VARYING  TIMES  OF  YEAR  AND  VALUES 
OF  PROGRESSIVE    RAINFALL  INDEX    TO  ABSORB   EXCESSIVE   FLOOD  FLOWS 


■  2411 — Page    84 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  85 

(5300  seeond-feet)  for  rain-water  floods  and  40  per  cent  (7100  second- 
feet)  for  snow-water  floods  indicate  valnes  of  130  and  120,  respectively. 
These  are  the  index  valnes  of  the  ontside  cnrves  on  the  operating 
diagram  whose  apices  indicate  respectively  on  the  reservoir  space  scale 
the  niaximnm  empty  space  of  92,000  acre-feet  for  rain-water  floods  and 
13.000  acre-feet  for  snow-water  floods. 

The  interior  cnrves  are  drafted  in  comparison  witli  the  exterior 
curves  after  interpolating  the  positions  of  their  apices  between 
that  of  the  outside  curve  and  the  line  of  zero  reservoir  space  and  the 
positions  of  tlie  arms  of  the  curves  between  the  limiting  and  central 
dates  of  the  flood  season  as  in  the  preparation  of  the  Sacramento  River 
diagram.  There  is  one  black  curve  for  each  increment  of  10  in  the 
progressive  rainfall  index  valnes  less  than  that  most  favorable  for  the 
need  of  reservoir  space  to  control  floods  and  one  red  curve  for  each 
similar  increment  greater  than  the  most  favorable  value.  The  values  of 
the  progressive  rainfall  index  that  apply  to  the  curves  of  smallest  and 
largest  valnes  whicli  are  coincident  with  the  line  of  zero  reservoir  space 
on  tlie  operating  diagram,  and  above  and  below  which  reservoir  space  is 
not  needed  to  control  floods,  are  obtained  from  Plate  XVI,  p.  66.  On 
the  i)art  pertaining  to  rain-water  floods,  the  intersections  of  the  dotted 
and  full-line  curves  labeled  30  per  cent  (5300  second-feet)  with  the 
vertical  representing  two  days  in  100  years  on  which  values  will  be 
exceeded,  yield  limiting  values  of  the  ])rogressive  rainfall  index  of 
58  and  222;  while  on  the  part  pertaining  to  snow-water  floods,  the  inter- 
sections of  the  dotted  and  full-line  curves  labeled  40  per  cent  (7100 
second-feet)  yield  limiting  values  of  85  and  153. 

Reservoir  operating  diagram  for  controlling  floods   on   San  Joaquin   River. 

The  rule  for  operating  a  reservoir  on  the  San  Joaquin  River  for  flood 
control  is  delineated  on  Plate  XX,  "Reservoir  Operating  Diagram  for 
Controlling  Floods  on  San  Joaquin  River."  This  diagram  is  quite 
the  same  as  the  one  for  the  Mokelumne  River  except  tliat  snow-water 
floods  become  relatively  more  important  and  require  more  reservoir 
space  for  their  control  than  rain-water  floods.  The  nuiximnm  space 
re(juired  to  conti-ol  I'ain-Avater  floods  is  133,000  acre-feet  while  177,000 
acre-feet  are  required  for  the  conti'ol  of  snow-water  floods.  This  maxi- 
mum space  for  rain-water  floods  is  needed  on  January  18th  and  for 
snow-Avater  floods  on  June  4th  wlien  the  values  of  the  progressive  rain- 
fall index  are  122  and  110,  respectively.  The  space  required  on  these 
and  other  dates  when  the  index  values  are  less  than  122  for  rain-water 
and  110  for  snow-water  floods,  is  indicated  by  the  several  black  curves 
labeled  with  smaller  index  values.  The  red  curves  indicate  the  space 
required  when  the  index  values  exceed  122  and  110,  respectively. 

The  diagram  applies  to  any  reservoir  within  a  distance  of  about  30 
miles  upstream  from  Friant,  the  point  of  measurement  on  the  San  Joa- 
quin River.  With  a  capacity  greater  than  177,000*  acre-feet  the  appli- 
cation of  the  rule  would  result  in  limiting  rain-water  floods  to  a 
maximum  flow  of  10,700  second-feet  and  snow-water  floods  to  a  maxi- 
mum flow  of  14,200  second-feet  at  the  i)oint  of  nu'asurement.  It  is 
estimated,   because  of  diversions  for   irrigation   from   the  snow-water 

*  The  reservoir  space  needed  for  flood  control  in  addition  to  177,000  acre-feet  is 
that  which  would  furnish  the  minimum  operating  head  on  the  reservoir  outlets  to  dis- 
charge 14,200  second-feet. 


86  WATER   RESOURCES   OP    CALIFORNIA. 

flows  and  accretions  to  the  rain-water  run-off  downstream  from  the 
point  of  measurement,  that  these  two  regulations  will  produce  approxi- 
mately an  equivalent  effect  in  the  lower  channel  of  the  river. 

With  the  exception  of  a  small  fall  flood  occurring  on  October  2,  1918, 
M'ith  a  mean  daily  discharge  of  10,900  second-feet,  the  diagram  will 
control  all  floods  shown  in  the  eighteen  years  of  continuous  record  by 
the  United  States  Geological  Survey.  The  flood  of  January  31,  1911, 
with  a  mean  daily  flow  of  38,800  second-feet  was  the  largest  during 
this  period.  It  was  28,100  second-feet  greater  than  the  maximum  con- 
trolled rain-Avater  flow  that  would  be  obtained  by  application  of  the 
diagram.  The  largest  snow-water  flood  during  the  period  occurred  on 
June  13,  1911,  when  the  mean  daily  flow  was  23,100  second-feet.  This 
is  8900  second-feet  larger  than  the  maximum  controlled  snow-w'ater 
flow  that  would  be  obtained  by  application  of  the  diagram. 

The  San  Joaquin  River  diagram  was  constructed  from  data  taken 
from  the  analytical  graphs  of  Chapter  IV  in  a  way  identical  to  that 
for  the  construction  of  the  diagrams  for  the  Sacramento  and  Mokelumne 
rivers.  The  same  probability  that  the  desired  maximum  controlled  flow 
may  be  exceeded  on  an  average  of  one  day  in  50  years  was  used.  The 
values  of  the  i)rogressive  rainfall  index  for  the  San  Joaquin  River 
were  computed  from  the  records  of  the  United  States  Weather  Bureau 
at  Fresno.*  This  station  sliould  be  used  for  determining  the  index 
values  in  applying  the  diagram. 

The  positions  of  the  apices  of  the  outside  curves  along  the  scale  of 
reservoir  space  are  taken  from  Plate  XII,  p.  57.  Reading  the  30  per 
cent  curve  (10,700  second-feet)  for  rain-water  floods  and  the  40  per  cent 
curve  (14,200  second-feet)  for  snow-water  floods,  it  is  seen  that,  for 
full  control  except  probably  on  an  average  of  two  days  in  100  years, 
the  maximum  space  required  is  188  per  cent  of  the  greatest  daily 
run-off  of  a  onee-in-25-year  flood  (133,000  acre-feet)  for  the  control  of 
rain-water  floods,  and  250  per  cent  (177,000  acre-feet)  for  the  control 
of  snow-water  floods. 

The  dates  on  which  this  maximum  space  is  required,  the  culminating 
dates  of  tiie  two  flood  seasons,  are  taken  from  the  lower  figure  of  Plate 
XIV,  p.  64.  On  tlie  part  of  the  figure  pertaining  to  rain-w'ater  floods,  the 
intersection  of  the  dotted  and  full-line  curves  labeled  30  per  cent  (10,700 
second-feet)  shows  this  to  be  January  18th.  On  the  part  pertaining 
to  snow-water  floods,  the  intersection  of  the  dotted  and  full-line  curves 
labeled  40  per  cent  (14,200  second-feet)  shows  this  date  to  be  June  4th. 

The  arms- of  the  outside  curves  of  the  diagram  have  their  positions 
defined  by  the  limiting  dates  of  the  flood  season  taken  from  the  lower 
figure  on  Plate  XIV,  p.  64.  Here,  on  the  part  pertaining  to  rain-water 
floods,  the  intersections  of  the  two  30  per  cent  (10,700  second-feet) 
curves,  one  dotted  and  one  full-line,  with  the  vertical  representing 
two  days  in  100  years  on  which  some  reservoir  space  is  needed  to  con- 
trol floods,  give  October  22d  and  April  7th.  Similarly,  on  the  part 
of  the  figure  pertaining  to  snow-water  floods,  the  two  40  per  cent  curves 
(14,200  second-feet)  intersect  the  same  vertical  at  April  27th  and 
July  16th.    These  are  tlie  limiting  dates  of  the  two  flood  seasons  before 

*  Fresno  is  one  of  the  princiiial  stations  in  precipitation  division  Q  of  which  the 
San  Joaquin  drainage  ba.sin  is  part.  See  Chap.  II,  Bui.  5,  "Flow  in  California  Streams," 
issued  by  the  Division  of  Engineering  and  Irrigation,  State  Department  of  Public 
Works. 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  87' 

and  after  which  reservoir  space  is  not  needed  to  control  floods.  The 
positions  of  the  arms  of  the  interior  curves  and  their  shapes  were  deter- 
mined as  for  the  Sacramento  and  Mokelumne  river  diagrams. 

The  index  values  with  which  the  maximum  reservoir  space  is  needed 
were  obtained  from  Plate  XVII,  p.  67.  Here  the  intersections  of  the 
full  and  dotted-line  curves  labeled  80  per  cent  (10,700  second-feet) 
for  rain-water  floods  and  40  per  cent  (14,200  second-feet)  for  snoAV- 
Avater  floods  indicate  values  between  110  and  122  as  being  most  favor- 
able for  the  need  of  reservoir  space  to  control  both  rain  and  snow-water 
floods.  These  are  the  index  values  of  the  outside  curves  of  the  diagram. 
The  index  values  for  the  extreme  inside  curves  are  taken  from  the  same 
plate.  On  the  part  pertaining  to  rain-water  floods,  the  intersections  of 
the  two  30  per  cent  (10,700  second-feet)  curves,  one  dotted  and  one 
full-line,  with  the  vertical  representing  two  days  in  100  years  on  which 
values  will  be  exceeded,  indicate  limiting  values  of  the  index  of  49  and 
183.  Keservoir  space  is  not  needed  to  control  floods  with  either  smaller 
or  larger  values  than  these.  On  the  part  of  the  figure  pertaining  to 
snow-water  floods,  the  corresponding  limiting  values  are  found  to  be 
73  and  139.  The  index  values  for  the  several  interior  curves  on  the 
operating  diagram  are  interpolated  between  these  and  the  values  for 
tlie  outside  curve  the  same  way  as  for  the  diagrams  of  the  Sacramento 
find  IMokelumne  rivers. 

Reservoir  operating  diagram  for  controlling  floods  on   San   Gabriel    River. 

Plate  XXI,  "Reservoir  Operating  Diagram  for  Controlling  Floods 
on  San  Gabriel  River,"  delineates  the  rule  for  operating  a  reservoir  on 
this  stream  in  order  to  control  floods  with  least  interference  in  its  con- 
servation use.  Like  the  diagrams  for  the  Sacramento,  Mokelumne  and 
San  Joaquin  rivers,  that  for  the  San  Gabriel  indicates  the  space  that 
should  be  empty  on  each  day  of  the  flood  season  for  the  amount  of 
seasonal  precipitation  to  date,  in  order  that  excess  flood  waters  may  be 
detained.  The  curves  in  black  indicate  the  space  that  should  be  empty 
when  the  value  of  the  progressive  rainfall  index  is  less  than  120  and 
the  red  curves  the  space  when  the  value  is  greater  than  130.  The  dia- 
gram assumes  that  the  reservoir  outlet  gates  will  be  opened  and  closed 
as  may  be  necessary  to  pi'ovide  within  24  hours  as  nearly  as  possible, 
without  causing  the  desired  regulated  flow  to  be  exceeded,  the  empty 
space  indicated  on  the  diagram  for  the  current  day  and  value  of  progres- 
sive rainfall  index. 

The  San  Gabriel  River  diagram  is  like  that  for  the  Sacramento  River 
in  that  it  does  not  provide  for  the  control  of  snow^-water  floods.  The 
snow  on  the  San  Gabriel  drainage  area  that  lasts  until  early  summer 
is  too  small  in  quantity  to  do  more  than  help  sustain  the  summer  flow 
of  the  stream  when  it  melts. 

The  diagram  applies  to  any  reservoir  whose  dam  is  within  a  distance 
of  about  5  miles  upstream  from  the  Azusa  gaging  station,  the  point 
of  measurement.  A  capacity  of  131,000  acre-feet  available  for  flood 
control  purposes  would  be  required.  The  application  of  the  rule  to  the 
operation  of  a  reservoir  of  this  or  greater  capacity  would  result  in 
limiting  flood  flows  to  1900  second-feet  at  Azusa  gaging  station.  A 
much  larger  flow  than  this  will  pass  safely  down  the  channel  of  the 
San  Gabriel  River  to  the  ocean  but  it  could  not  all  be  conserved.    It  is 


88  WATER    RESOURCES    OF    CALIFORNIA. 


PLATE  XXL 

0                             30                            60                            90                            120                          150 

20 
^"'^  ,0 

20 

June 

10 

Reservoir  outlet  gates  to  be  opened  or  closed  daily  as  may  be 
necessary  to  provide  within  24  nours  The  unoccupiec  space  indi- 
cated on  diagram  for  the  current  daji  and  value  of  progressive 
rainfall  Index.  Release  from  reservoir  limited  in  rate  in  order  that, 
in  combining^  with  run-off  downstream  from  reservoir  the  maximum 
controlled  flow  will  not  be  exceeded  at  point  of  measurement. 
Curved  lines  on  diagram  are  marked  with  values  of  the  pro- 
gressive rainfall  index.  Black  lines  are  used  for  valuesof 
130  or  less  and  red  lines  for  greater  values. 

20 

May 

^    10 

20 

April  ^ 

10 

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^^^ 

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20 

Mar. 

10 

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20 

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Progressive  rainfall  index  / 

^\ 

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20 

Oct. 

10 

1         ; 

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0                             30                            60                             90                           120 

Reservoir  space  in  thousands  of  acre  feet 

15 

0 

Reservoir  Operating  Diagram 
FOR  Controlling  Floods  on  San  Gabriel  River 

MAXIMUM  CONTROLLED  FLOW  NEIAR  AZUSA-  1,900  SEC.  FT. 

CURVES  SHOW    SPACE  NEEDED  AT  VARYING  TIMES  OF  YEAR  AND  VALUES 
OF  PROGRESSIVE   RAINFALL  INDEX  TO  ABSORB  EXCESSIVE  FLOOD  FLOWS. 

.24  11 — Page    8S 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  89 

believed  that  flows  up  to  1900  seeond-feet  may  be  conserved  conven- 
iently by  sinking  tlieni  into  the  large  underground  basin  of  the  San 
Gabriel  Valley.  This  makes  it  desirable  to  reduce  the  San  Gabriel 
River  floods  to  a  much  smaller  flow  than  on  the  other  illustrative 
streams. 

The  largest  flood  in  the  thirty  years  of  stream  flow  record  at  Azusa 
occurred  on  January  18,  1916.  with  a  crest  flow  of  40,000  second-feet. 
This  is  38,100  second-feet  greater  than  the  controlled  flow  that  would 
result  from  the  application  of  the  diagram.  The  greatest  mean  daily 
flow  of  the  1916  flood  was  22,300  second-feet. 

The  diagram  for  the  San  Gabriel  River  was  constructed  from  the 
analytical  graphs  of  Chapter  IV  in  a  manner  similar  to  that  employed 
in  the  construction  of  diagrams  for  the  other  three  illustrative  streams. 
Instead,  however,  of  using  the  probability  that  the  desired  maximum 
controlled  flow  may  be  exceeded  on  an  average  of  one  day  in  50 
years  in  taking  information  from  the  charts  as  in  the  preparation 
of  the  other  diagrams,  a  frequency  of  one  day  in  a  thousand  years  was 
selected  because  of  the  greater  property  A'^alues  and  population  concen- 
trating below  the  San  Gabriel  dam.  The  records  of  the  United  States 
Weather  Bureau  rainfall  station  at  Claremont*  were  used  in  computing 
values  of  the  progressive  rainfall  index  for  the  San  Gabriel  River. 
This  is  the  station  that  should  be  used  in  the  application  of  the 
diagram. 

The  apex  of  the  outside  curve  on  the  San  Gabriel  diagram  has  its 
position  determined  on  the  reservoir  space  scale  from  the  largest 
empty  space  that  is  required  under  the  most  severe  circumstances  as 
shown  on  the  lower  figure  of  Plate  X,  p.  55.  The  intersection  of  the 
10  per  cent  curve  (1900  second-feet)  with  the  vertical  representing 
full  control  except  on  an  average  of  0.1  day  in  100  years  (one  day  in 
1000  years)  shows  that  the  maximum  reservoir  space  required  is  344 
per  cent  of  the  greatest  daily  run-off  of  a  once-in-25-year  flood  (131,000 
acre-feet).  Its  position  on  the  time  scale  is  fixed  by  the  date  most 
favorable  for  the  need  of  reservoir  space  for  the  control  of  floods.  This 
is  taken  from  the  lower  cut  on  Plate  XIII,  p.  63.  The  intersection  of 
the  dotted  and  full-line  curves  labeled  10  per  cent  (1900  second-feet) 
indicates  February  7th  as  the  most  favorable  date. 

The  positions  of  the  arms  of  the  outside  curve  of  the  diagram 
are  also  determined  from  Plate  XIII,  p.  63.  Here  the  dotted 
and  fidl-line  curves  labeled  10  per  cent  (1900  second-feet)  intersect 
the  vertical  of  0.1  day  exceptional  behavior  in  100  years  (one  day  in 
1000  years)  on  October  27th  and  April  19th,  respectively.  These  are 
the  limiting  dates  of  the  flood  season  before  and  after  which  reservoir 
space  is  not  needed  for  the  control  of  floods  to  the  degree  selected. 

The  value  of  the  progressive  rainfall  index  with  which  the  greatest 
reservoir  space  is  needed  is  taken  from  the  lower  figure  of  Plate  XV, 
p.  65.  The  intersection  of  the  full  and  dotted-line  curves  labeled  10 
per  cent  (1900  second-feet)  marks  tlie  index  value  122  as  being  most 
favorable  for  the  need  of  reservoir  space.  The  outside  curve  that 
indicates  the  need  of  most  s])ace  is  given  a  value  of  from  120  to  130. 

*  Claremont  i.s  a  cooijcrativo  station  of  the  United  States  Weatlier  Buroau  and 
ono  of  the  principal  station.s  in  precipitation  divi.sion  W  of  which  the  San  Gabriel 
(Irainagre  basin  is  part.  See  Chap.  II.  Bui.  No.  .^),  "Flow  in  California  Streams," 
issued  by  Division  of  Engineering  and  Irrigation,  State  Department  of  Public  Works. 


90  WATER   RESOURCES   OF    CALIFORNIA. 

The  index  value  for  the  extreme  inside  curve  is  taken  from  the  same 
plate.  The  intersections  of  the  two  curves,  one  dotted  and  one  full-line, 
labeled  10  per  cent  (1900  second-feet)  with  the  vertical  on  the  extreme 
left  representing  an  exceptional  behavior  of  0.1  day  in  100  years  (one 
day  in  1000  years),  give  limiting  values  for  the  index  of  27  and  294. 
Reservoir  space  is  not  needed  for  controlling  floods  when  the  index  is 
either  smaller  or  larger  than  tliese  values.  Therefore,  27  and  294  are 
the  index  values  of  the  black  and  red  curves  respectively  that  are  coin- 
cident with  the  line  of  zero  reservoir  space.  The  other  interior  curves 
are  interpolated  in  position  between  these  and  the  outside  curve  as  in 
the  construction  of  the  diagrams  for  the  other  three  illustrative  streams. 

Performance  of  the  four  illustrative  reservoir  operating  diagrams  in  controlling 
floods,  not  coordinated  with  conservation. 

The  performance  in  controlling  floods  of  the  four  reservoir  operating 
diagrams  just  described  has  been  tested  by  applying  them  respectively 
to  the  records  of  daily  flow  on  each  of  the  four  illustrative  streams. 
It  was  assumed  that  a  reservoir  of  required  capacity  existed  at  the  point 
of  measurement  on  each  stream,  that  it  was  full  at  the  beginning  of 
each  flood  season,  that  it  was  held  as  nearly  full  as  the  diagram  Avould 
])ermit  during  the  succeeding  flood  season,  and  that  water  was  released 
from  storage  only  as  required  to  gain  the  empty  space  indicated  on  the 
diagram.  The  following  tables  sliow  for  all*  tlie  largest  floods  of 
record,  both  rain  and  snow-water,  the  dates  on  whicli  the  reservoirs 
would  have  been  nearest  full  and  the  amount  of  space  still  empty  ou 
those  daj'^s. 

It  may  be  noted  that  all  floods  of  record  on  the  four  illustrative 
streams  would  have  been  controlled  witliout  the  reservoirs  overflowing 
except  a  small  fall  flood  on  the  San  Joatiuin,  occurring  on  October  2, 
1918,  with  a  discharge  of  only  200  second-feet  in  excess  of  the  maxi- 
mum controlled  flow.  On  the  Sacramento  River  even  tlie  liistoric  floods 
of  March  20,  1907,  and  February  3,  1909.  would  have  been  controlled 
with  53,500  and  188,800  acre-feet  of  space  to  spare  respectively  at  the 
times  the  reservoir  was  nearest  full.  The  average  space  to  spare  at 
the  times  nearest  full  while  controlling  all  floods  on  the  Sacramento 
River  during  the  entire  thirty  years  of  record  would  have  been  e(|ual 
to  half  the  space  required  under  the  most  severe  circumstances. 

•  All  floods  exceeding  the  desired  maximum  regulated  flow  are  listed  when  their 
number  is  less  than  twenty,  otherwiae  the  twenty  largest  are  tabulated. 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS. 


91 


SACRAMENTO  RIVER 

UNUSED  RESERVOIR  SPACE 

WHILE  CONTROLLING  ALL  FLOODS  OF  RECORD  BY  RESERVOIR 
OPERATING  DIAGRAM  1895-1926 

Not  Coordinated  with  Conservation 


Maximum  flood  flow — uncontrolled 

Flow  controlled  to  125,000  second-feet  ma.timum  near  Red  Bluff 

Reservoir  space  not  used  in 

controlling  flood 

Mean  daily 
flow  in  second- 

Date  reservoir  nearest 

Date 

feet  near 

full 

In  per  cent  of  maxi- 

Red Bluff 

In  acre-feet 

mum  space  required 

for  flood  control 

(454,000  acre-feet) 

Feb.    3,  1909 

254,000 

Feb.    4,  1909 

188,800 

42 

Feb.     2.  1915 

249,000 

Feb.     2,  1915 

200,900 

44 

Mar.  20,  1907 

196,000 

Mar.  21,  1907 

53,500 

12 

Jan.   16,  1909 

188,000 

Jan.   18,  1909 

191,400 

42 

Feb.  16,  1904 

188,000 

Feb.  16,  1904 

357,700 

79 

Jan.  21,  1909 

177,000 

Jan.  21,  1909 

150,700 

33 

Feb.  25,  1917 

176,000 

Feb.  25,  1917 

109,300 

24 

Feb.  21,  1914 

160,000 

Feb.  21,  1914 

119,600 

26 

Jan.     1,  1914 

151,000 

Jan.     2, 1914 

129,900 

29 

Feb.  24,  1902 

151,000 

Feb.  26,  1902 

289,100 

64 

Mar.    8,  1904 

147,000 

Mar.    8,  1904 

332,400 

73 

Feb.  10,  1902 

140,000 

Feb.  12,  1902 

327,600 

72 

Mar.  31,  1906 

137,000 

Mar.  31,  1906 

105,500 

23 

Jan.   19,  1906 

136,000 

Jan.   19,  1906 

143,600 

32 

Feb.    4,  1907 

134,000 

Feb.    4,  1907 

433,500 

95 

Jan.  25,  1903 

131,000 

Jan.  25,  1903 

431,700 

95 

Mar.    7,  1911 

130,000 

Mar.   7,  1911 

368,400 

81 

Jan.  27,  1896 

128,000 

Jan.  27,  1896 

341,500 

75 

Average 

237,500 

52 

I 


92 


WATER   RESOURCES   OF    CALIFORNIA, 


MOKELUMNE  RIVER 

UNUSED  RESERVOIR  SPACE 

WHILE  CONTROLLING  TWENTY  LARGEST  RAIN  WATER  FLOODS  OF 
RECORD  BY  RESERVOIR  OPERATING  DIAGRAM  1904-1926 

Not  Coordinated  with  Conservation 


Maximum  flood  flow— uncontrolled 

Flow  controlled  to  5300  second-feet  maximum  near  Clements 

Reservoir  space  not  used  in 

controlling  flood 

Mean  daily 
flow  in  second- 

Date  reservoir  nearest 

Date 

feet  near 

full 

In  per  cent  of  maxi- 

Clements 

In  acre-feet 

mum  space  required 
for  flood  control 
(92,000  acre-feet) 

Jan.  30,  1911 

16,700 

Feb.    1,  1911 

35,200 

38 

Mar.  19,  1907 

15,310 

Mar.  27,  1907 

7,100 

8 

Jan.  2C).  1914 

11,100 

Jan.  27,  1914 

68,900 

75 

Jan.   14,  1909 

10,400 

Jan.   17,  1909 

5,200 

6 

Feb.  21,  1914 

9,850 

Feb.  21,  1914 

82,700 

90 

Feb.    6,  192.5 

9,700 

Feb.     6,  1925 

27.800 

30 

Jan.     1, 1914 

9,250 

Jan.     1,  1914 

36,100 

39 

.Tan.  21,  1909 

8.400 

Jan.   22,  1909 

8,500 

9 

Mar.  20,  1916 

8,040 

Mar.  21,  1916 

64,400 

70 

Feb.     2,  1907 

7,860 

Feb.     4,  1907 

79,300 

86 

Mar.  31,  190tj 

7.750 

.\pril    1,  1906 

49,600 

54 

Mar.  23,  1907 

7,610 

Mar.  27,  1907 

7,100 

8 

Jan.  22, 1914 

7,47i) 

,Ian.   22,  1914 

78,600 

85 

,Jan.   18,  1921 

7,350 

,Tan.   18,  1921 

75,700 

82 

Mar.    7,  1911 

7,210 

Mar.  11,  1911 

70,900 

77 

Nov.  21,  1909 

7,200 

Nov.  21   1909 

0 

0    . 

Feb.  11,  1919 

7,060 

Feb.  11,  1919 

29.000 

32 

Jan.   19,  190(i 

■  6,960 

Jan.    19,  1906 

24,400 

27 

Mar.  12,  1918 

6,940 

Mar.  12,  1918 

9,400 

10 

.\pril  16,  192.5 

6,910 

.■^pril  17,  1925 

6,600 

7 

Average 

38,300 

42 

THE  CONTROL  OF  FLOODS  BY  RESERVOIRS. 


93 


MOKELUMNE  RIVER 

UNUSED  RESERVOIR  SPACE 

WHILE  CONTROLLING  ALL  SNOW  WATER  FLOODS  OF  RECORD  BY 
RESERVOIR  OPERATING  DIAGRAM  1904-1926 


Not  Coordinated  with  Conservation 

Maximum  flood  flow— uncontrolled 

Flow  controlled  to  7100  second-feet  maximum  near  Clements 

Reservoir  space  not  used  in 

controlling  flood 

Mean  daily 
flow  in  second- 

Date  reservoir  nearest 

Date 

feet  near 

full 

In  per  cent  of  maxi- 

Clements 

In  acre-feet 

mum  space  required 

for  flood  control 

(13,000  acre-feet) 

June  12,  1906 

8,740 

June  13,  1906 

1,900 

15 

June  18,  1911 

8,030 

June  18,  1911 

3,300 

25 

June    3,  1922 

7,970 

June    5,  1922 

2,600 

20 

June  12,  1911 

7,960 

June  12,  1911 

3,100 

24 

June    6,  1911 

7,880 

June    6,  1911 

4,000 

31 

May  31,  1922 

7,770 

June    1,  1922 

6.700 

52 

June    1,  1915 

7,750 

June    1,  1915 

10,000 

77 

May  18,  1922 

7,670 

May  19,  1922 

1,800 

14 

June  16,  1906 

7,600 

June  17,  1906 

4,500 

35 

June  10,  1917 

7,550 

June  10,  1917 

2,900 

22 

May  24,  1911 

7,500 

May  24,  1911 

800 

6 

July     4,  1906 

7,480 

July    4,  1906 

1,100 

8 

Average 

3,600 

28 

SAN  JOAQUIN  RIVER 

UNUSED  RESERVOIR  SPACE 

WHILE   CONTROLLING   ALL   RAIN   WATER   FLOODS   OF   RECORD   BY 
RESERVOIR  OPERATING  DIAGRAM  1907-1926 

Not  Coordinated  with  Conservation 


Maximum  flood  flow — -uncontrolled 


Flow  controlled  to  10700  second-feet  maximum  near  Friant 


I 


Reservoir  space  not  used  in 

contrr 

lling  flood 

Mean  daily 
flow  in  second- 

Date  reservoir  nearest 

Date 

feet  near 

full 

In  per  cent  of  maxi- 

Friant 

In  acre-feet 

mum  space  required 

for  flood  control 
(133,000  acre-feet) 

Jan.  31,  1911 

38,800 

Feb.     1,  1911 

14,200 

11 

Dec.  31,  1909 

27,900 

Jan.     1,  1910 

43.600 

33 

Jan.   14,  1909 

26,800 

Jan.   15,  1909 

16,400 

12 

Dec.  10.  1909 

26  800 

Dec.  10,  1909 

28.200 

21 

Jan.  26,  1914 

24,700 

Jan.  30,  1914 

13,800 

10 

Jan.  21,  1909 

18,900 

Jan.  22,  1909 

62,700 

47 

Mar.    8,  1911 

18,800 

Mar.    8,  1911 

67,400 

51 

Mar.  10,  1911 

13,600 

Mar.  12,  1911 

55,900 

42 

Feb.  12,  1909 

12,500 

Feb.  14,  1909 

104,100 

78 

Feb.  21,  1917 

11,700 

Feb.  21,  1917 

100,700 

76 

April   6.  1911 

11,600 

April   6,  1911 

0 

0 

Jan.   18,  1916 

11,000 

Jan.  20, 1916 

113.100 

85 

Mar.  21,  1916 

11,000 

Mar.  21,  1916 

15,100 

11 

Oct.     2,  1918 

10,900 

Oct.     2,  1918 

0 

0 

Jan.  25,  1911 

10,700 

Jan.  25,  1911 

79,300 

60 

Average 

47,600 

36 

94 


WATER   RESOlTRf'ES   OF    CALIFORNIA. 


SAN  JOAQUIN  RIVER 

UNUSED  RESERVOIR  SPACE 

WHILE   CONTROLLING   ALL   SNOW   WATER   FLOODS   OF   RECORD   BY 

RESERVOIR  OPERATING  DIAGRAM  1907-1926 

Not  Coordinated  with  Conservation 


Maximum  flood  flow— uncontrolled 

Flow  controlled  to  14200  second-feet  maximum  near  Friant 

Reservoir  space  not  used  in 
controlling  flood 

Mean  daily 
flow  in  second- 

Date  reservoir  nearest 

Date 

1 

feet  near 

full 

1  In  per  cent  of  maxi- 

Friant 

In  acre-feet 

mum  space  required 
for  flood  control 
(177.000  acre-feet) 

June  13.  1911 

23.100 

June  23.  1911 

21,100 

12 

June    4,  1909 

22.800 

June    8.  1909 

89.100 

50 

June  16.  1911 

21.500 

June  23.  1911 

21.100 

12 

July     7.1911 

19.500 

July     7.  1911 

57,600 

33 

June    5.  1922 

16.700 

June    8,  1922 

149.700 

85 

May  22.  191 1 

16.200 

Mav  23.  1911 

134.600 

76 

June    fi.  1911 

16.200 

June    8.  1911 

165.500 

94 

May    8.  1909 

1O.200 

May    8,  1909 

39,300 

22 

June    2.  1914 

15.700 

June    2.  1914 

167,500 

95 

June    5.  1912 

15.300 

June    5.  1912 

33,000 

19 

June  15.  1909 

14.900 

June  15.  1909 

95.000 

54 

June  27.  1911 

14.700 

June  28.  1911 

38,200 

22 

May  31.  1922 

14.700 

June    1.  1922 

171.200 

97 

June  24.  1909 

14.600 

June  24.  1909 

129,300 

73 

.\veraEf 

93,700         1                  53 

SAN  GABRIEL  RIVER 

UNUSED  RESERVOIR  SPACE 

WHILE   CONTROLLING   TWENTY   LARGEST   FLOODS   OF   RECORD   BY 

RESERVOIR  OPERATING  DIAGRAM  1895-1926 

Not  Coordinated  with  Conservation 


Maximum  flood  flow — uncontrjUed 

Flow  cantrolled  to  1900  second-feet  maximum  near  Azusa 

Reservoir  space  not  used  in 

controlling  flood 

Mean  daily 
flow  in  S3cond- 

Date  reservoir  nearest 

Date 

feet  nerr 

full 

In  per  cent  of  maxi- 

.\zusa 

In  acre-feet 

raim  space  required 
for  n lod  f introl 
(131.000  acre-feet) 

.Ian.   18,  1916 

22.300 

Jan.  20,  1916 

45,300 

35 

Dec.  19.  1921 

16.000 

Dec.  25.  1921 

25.000 

19 

Jan.     1,  1910 

12.500 

.Ian.     3.  1910 

82.100 

63 

Feb.  20,  1914 

11.800 

Mar.    1.  1914 

64.,500 

49 

Mar.  12,  1905 

11.130 

Mar.  14.  1905 

87.100 

66 

Mar.  26,  1906 

9.4.30 

Mar.  29.  1906 

29.100 

22 

Mar.  10,  1911 

9.160 

Mar.  14.  1911 

71.400 

54 

Jan.  26,  1914 

9.1.50 

Jan.   27.  1914 

911.200 

76 

Feb.     9,  1922 

8.200 

Feb.   13.  1922 

68.(100 

S3 

Mar.  12.  1906 

8.020 

M:ir.  13.  I'.Mm 

88.900 

68 

Jan.   27.  1916 

7,940 

Jan.   30.  r.illl 

37.100 

28 

Feb.     7.  1909 

7.100 

Feb.     8.  I'.m.i 

118.100 

90 

Mar.    5.  1907 

6.810 

Mar.  11.  r.Ml7 

S.t.900 

69 

April    1.  1903 

5.920 

.\oril   2.  1903 

95.400 

73 

Dec.  27,  1921 

5.900 

Dec.  29.  1921 

12.700 

10 

Jan.  29.  1911 

5.260 

.Ian.   29.  1911 

80.400 

61 

Jan.   IH.  1914 

.5.110 

Jan.    18.  1914 

103.000 

79 

Mar.  11.  1918 

5.030 

.Mar.  U.  1918 

21.E00 

16 

Jan.   10,  I!K)7 

4.670 

Jan.   11.  1907 

108.600 

83 

Jan.  31,  1911 

4.220 

Jan.   31,  1911 

76.200 

58 

.\veragc 

70.200 

54 

THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  95 

On  the  Mokehimne  River,  the  large  flood  of  January  30,  1911,  would 
have  been  reduced  from  20,600  second-feet  to  5300  second-feet  with 
35,200  acre-feet  of  empty  space  in  the  reservoir  to  spare  at  the  time 
the  reservoir  was  nearest  full.  The  average  spare  space  at  the  times 
nearest  full  while  controlling  the  twenty  largest  rain-water  floods  on 
the  Mokelumne  River  would  have  been  42  per  cent  of  the  maximum 
required  by  the  diagram.  One  small  flood  in  the  fall  of  1909  would 
•have  just  filled  the  reservoir  but  there  would  have  been  more  space 
than  needed  while  controlling  all  other  floods. 

On  the  San  Joaquin  River,  the  largest  flood  during  the  eighteen 
years  of  record  (January  31,  1911)  would  have  been  reduced  from  a 
mean  daily  flow  of  38,800  second-feet  to  10,700  second-feet  without 
the  use  of  the  top  14,200  acre-feet  in  the  reservoir.  The  average  unused 
space  at  the  times  the  reservoir  was  nearest  full  while  controlling  all 
rain-w^ater  floods  would  have  been  36  per  cent  of  the  maximum  space 
required  by  the  diagram.  There  would  have  been  space  to  spare  while 
controlling  all  floods  during  the  eighteen  years  of  record  except  for 
two  small  floods  barely  larger  than  the  controlled  flow.  One  of  these 
occurred  before  the  opening  date  of  the  flood  season,  on  October  2,  3918, 
and  the  other  on  April  6,  1911,  the  closing  date  of  the  flood  season. 
All  the  snow-water  floods  of  record  on  the  San  Joaquin  River  would 
have  been  controlled  without  the  reservoir  filling  to  within  21,100 
acre-feet  of  the  top.  The  average  space  to  spare  at  the  times  nearest 
full  while  controlling  snow-water  floods  would  have  been  53  per  cent 
of  the  maximum  required  by  the  diagram. 

On  the  San  Gabriel  River,  the  large  flood  of  January  18,  1916, 
would  have  been  controlled  without  the  use  of  the  top  45,300  acre-feet 
of  reservoir  space.  The  nearest  the  reservoir  would  have  filled  while 
controlling  all  floods  during  the  30  years  of  record  would  have  been  to 
12,700  acre-feet  of  a  full  reservoir.  The  average  unused  space  at  the 
times  nearest  full  during  the  twent}^  largest  floods  of  record  would 
have  been  54  per  cent  of  the  maximum  required  by  the  diagram. 

The  full  test  of  the  four  reservoir  operating  diagrams  is  expressed 
graphically  on  Plate  XXII,  ''Performance  of  Reservoir  Operating 
Diagrams  in  Controlling  Floods  of  Record."  The  ratio  of  the  empty 
reservoir  space  provided  by  application  of  the  diagrams  to  that  actually 
necessary  to  control  the  remainder  of  the  flood  was  computed  for  every 
day  of  stream-flow  record  on  each  of  the  four  illustrative  streams.  The 
ratios  on  each  stream  were  arranged  in  order  of  increasing  magnitude 
and  the  number  smaller  than  each  successive  size  counted.  These 
counts  were  increased  by  proportion  to  the  number  had  the  stream-flow 
records  been  100  years  in  length.  Assuming  that  the  trend  of  these 
figures  expresses  the  average  relations  of  the  future,  these  counts  were 
plotted  on  Plate  XXII  to  sliow  the  probable  frequency  witji  which  the 
empty  space  provided  by  application  of  the  diagrams  will  approach 
the  exact  amount  needed  to  secure  the  desired  control. 

Plate  XXII  indicates  that  tlic  Sacramento  River  diagram  would 
probably  provide,  on  the  average,  more  than  twice  the  empty  reservoir 
space  actually  required  on  all  days  except  30  in  each  100-year  period, 
more  than  half  again  as  much  as  needed  on  all  days  except  12  in  each 
100-year  period  and  that  its  reservoir  would  probably  fill  to  overflow- 
ing about  one  dav  in  each  80  vear.s.     For  the  Mokelumne  River  dia 


WATER   HEROTTRCES   OF    CAT.TFORNTA. 


PLATE  XXII. 


1 



<u 

SACRAMENTO  RIVER 

Z3 

Near  Red  Bluff 

L. 

..!_ — 

"to 

i 

1/) 

I 

'b 

V 

\ 

\ 

fO 

V 

O 
O 

i_ 

-lU- 

\ 

c 

\ 

en 

^ 

\ 

^ 

\ 

.£3 
E 

Z 

•100- 

•^ 

— 

— 



^ 

■    T' 

MOKELUMNE  RIVER 

Near  Clements 

Maximum  controlled  flow 

— 1 

— h 

-1 

• 

Snow 

water  floods  - 

i     '!' 

7,100 

sec  ft 

T 

""t 

1 

M      T 

1 

'  1     I! 

■ 

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-lOJ 

\ 

! 

\\ 

\  K 

:  III!  1 

\  j 

' 

\  ■ 

Ik 

'  1 

::i 



, 

V 

-V — i-  i-Snow  water  floods 

— ' 

ij 

^fTT^ 

■+4- 1 

■lUO- 

's; 

\ 

i- 

iH 

-: 

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/ 

[>- 

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Rain 

water  floods'' 

"•s. 

^1^1 

1 

Itrt 

-^ 

c::. 

• — 1 

-t 

— 

--H-4 

0.1 


100  0.1 


100 


<o 

SAN  GABRIEL  RIVER 

3 

Near  Aiusa 

>• 

_ 

--    _  \, 

aximum  controlled  flow   1,900  sec  ft. 

in 

"^ 

e 

«o 

i> 

— 1 

— 

— 

O 

o 

10 

c 

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m^ 

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T3 

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=) 

V 

\ 

1, 

> 

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,, 



U 

- 

- 

e^ 



B 

td 

bd 

:^ 

1 

ll':i 

SAN  JOAQUIN  RIVER 

Near  Friant 

_.  

Maximum  controlled  flow 

— . 

if 

1 

5n 

3W 

water 

floods  - 

4,2 

lOsec.ft^ 

oo(iofOct2,l9 
aliO'O 

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w 

1.900  stcond  fe 

fquircd  400  ac 

-10- 

;    I 

\ 

\ 

A 

J  •» 



— 

-3|r— 

Ua 

n  water  floods 

TOO- 

" 

\ 

\ 

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^H 

-^ 

; 

- 

■ 

A 

^-, 

Snow 

wter  floods- 

'  1  v.^_ 

H 

"* 



rr 

-::■■ 



= 

= 

I  10  100  0.1  I  10 

Ratio  of  reservoir  space  provided  to  that  actually'  required. 


100 


Performance  of  Reservoir  Operating  Diagrams 
IN  Controlling  Floods  of  Record 


CURVES  SHOW  NUMBER  OF  DAYS  IN   100  YEARS  ON  WHICH 

RATIO  OF  RESERVOIR   SPACE  PROVIDED  BY  APPLICATION  OF 

DIAGRAM  TO  THAT  ACTUALLY  REQUIRED   FOR   CONTROLUNG 

FLOODS  OF  RECORD  IS   SMALLER  THAN  INDICATED. 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  97 

gram,  the  indications  are  that  probably  more  than  twice  the  empty 
space  actually  needed  would  be  provided  on  the  average  on  all  days 
except  100  in  100  years  for  rain-water  floods  and  50  in  100  years  for 
snow^-water  floods ;  at  least  fifty  per  cent  more  than  actually  needed  on 
all  days  except  60  in  100  years  for  rain-water  floods  and  24  in  100  years 
for  snow-water  floods ;  and  that  the  reservoir  would  fill  to  overflowing 
on  two  to  three  days  in  100  years  for  both  rain  and  snow-water  floods. 
The  indications  for  the  San  Joaquin  River  diagram  are  that,  on  the 
average,  probably  more  than  twice  the  empty  space  actually  needed 
Avould  be  provided  on  all  days  except  70  in  100  years  for  rain-water 
floods  and  150  in  100  years  for  snow-water  floods;  at  least  half  again 
as  much  as  needed  on  all  days  except  43  in  100  years  for  rain-water 
floods  and  100  in  100  years  for  snow-water  floods;  and  that  the  reser- 
voir would  probably  fill  to  overflowing  on  three  days  in  100  years 
for  both  rain  and  snow-water  floods.  For  the  San  Gabriel  River,  the 
indications  are  that  probably  more  than  twice  the  empty  space  needed 
would  be  provided  on  all  days  except  120  in  each  100-year  period  at 
least  50  per  cent  more  than  actually  needed  on  all  days  except  50  in 
each  100  years,  and  that  the  reservoir  would  probably  fill  to  overflowing 
on  about  one  day  in  each  500  years. 

These  tests  agree  fairly  closely  with  the  probability  of  exceptional 
behavior  selected  for  construction  of  the  diagrams.  On  the  Sacramento, 
JMokelumne  and  San  Joaquin  rivers,  by  construction,  the  controlled 
flow  for  both  rain  and  snow-water  floods  would  be  expected  to  be 
exceeded  on  an  average  of  one  day  in  50  years.  By  test  against  the 
period  of  record  the  desired  controlled  flow  of  the  Sacramento  River 
diagram  would  probably  be  exceeded  on  an  average  of  one  day  in  80 
years  and  the  Mokelumne  and  San  Joaquin  river  diagrams  on  an 
average  of  one  day  in  30  to  40  years  for  both  rain  and  snow-water 
floods.  The  desired  controlled  flow  of  the  San  Gabriel  River  diagram 
by  construction  would  be  expected  to  be  exceeded  on  an  average  of 
one  day  in  1000  years.  By  test  against  the  period  of  record  the 
probable  exceptional  behavior  of  this  diagram  is  one  day  in  500  years. 


7—52411 


98  WATER   RESOURCES   OF    CALIFORNIA. 


CHAPTER  VI. 


EFFECT  ON  CONSERVATION  OF  CONTROLLING  FLOODS  BY 
RESERVOIR  OPERATING  DIAGRAM. 

Effect  determined   by  direct  test. 

Four  reservoir  operating  diagrams  are  described  in  chapter  V,  one 
for  controlling  floods  on  each  of  the  four  streams  previously  used  to 
illustrate  the  characteristics  of  flood  occurrence.  These  diagrams  indi- 
cate the  reservoir  space  for  all  conditions  of  prior  rainfall,  that  should 
be  empty  on  each  day  of  the  flood  season  in  order  to  detain  flow  that 
may  occur  in  excess  of  a  specified  maximum  rate.  Subsequent  to  the 
central  date  of  the  flood  season,  less  empty  space  is  required  as  the 
season  progresses  toward  its  close.  The  diagrams  are  constructed  to 
release  this  reserved  space  as  quickly  as  possible  without  sacrifice  in 
the  effectiveness  of  flood  control.  Therefore,  until  some  analysis  is 
developed  that  fits  the  characteristics  of  flood  occurrence  closer  than 
the  one  herein  described,  it  may  be  said  that  reservoir  operation  in 
accord  with  these  diagrams  secures  the  control  of  floods  with  a  mini- 
mum interference  with  the  use  of  the  same  space  for  conservation. 

To  what  extent,  if  any,  the  reservation  of  the  varying  amounts  of 
space  indicated  on  the  diagrams  may  interfere  with  its  use  for  conserva- 
tion is  not  apparent.  The  amount  of  the  reservations  relative  to  the 
volume  of  subsequent  run-off  determines  this  in  each  instance.  There- 
fore, it  is  evident  that  the  degree  of  flood  control  desired  and  the  regi- 
men of  the  stream  are  important  factors  in  determining  the  extent  of 
interference,  if  any.  Other  factors  are  the  size  of  the  reservoir  and 
the  manner  of  its  operation.  If  the  total  capacity  of  the  reservoir 
were  several  times  the  largest  reserve  required  for  flood  control,  there 
would  be  many  days  on  which  the  empty  space  due  to  normal  operation 
for  conservation  would  exceed  that  required  for  flood  control.  At 
such  times  there  could  be  no  interference  with  conservation  by  reason 
of  the  use  of  the  same  space  for  flood  control.  Therefore,  the  larger 
the  total  capacity  of  the  reservoir  in  proportion  to  the  maximum  flood 
control  reserve,  the  less  is  the  opportunity  for  interference.  Likewise 
the  opportunity  of  interference  is  less,  the  greater  the  seasonal  draw- 
down in  the  reservoir  or  the  smaller  the  spring  draft  subsequent  to  the 
central  date  of  the  flood  season  during  normal  operation  for  conserva- 
tion. Because  of  the  complication  of  these  relations,  the  determination 
of  the  effect  on  conservation  of  controlling  floods  by  the  reservoir 
operating  diagrams  must  be  made  through  the  analj'sis  of  each  specific 
proposal.  The  interference  or  approach  toward  interference  might 
well  be  different  for  each  stream,  each  degree  of  flood  control,  and  each 
size  of  reservoir  and  manner  of  operating  it  for  conserving  water. 

The  succeeding  pages  of  this  chapter  are  devoted  to  the  presentation 
of  analyses  of  the  effect  on  the  water  and  power  yield  of  combining 
flood  control  with  several  modes  of  operating  four  specific  reservoirs, 
one  on  each  of  tlie  illustrative  streams.  In  these  studies  eacli  reservoir 
is  assumed  to  have  been  in  existence  at  the  beginning  of  continuous 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  99 

measurement  of  flow  on  its  stream  and  to  have  been  operated  for  con- 
servation in  a  specific  manner  through  the  entire  period  of  stream  flow 
record  both  with  and  without  flood  control.  The  effect  on  conservation 
in  these  instances  of  the  use  of  the  same  space  for  both  flood  control  and 
conservation  is  determined  by  a  comparison  of  the  yield  of  water  and 
power  in  the  two  parallel  sets  of  computations.  In  these  computations 
the  inflow,  evaporation  and  drafts  from  the  reservoirs  are  balanced 
daily  and  the  new  reservoir  levels  tabulated  both  with  and  without  the 
reservation  of  space  for  flood  control  in  accord  with  the  operating 
diagrams.  In  doing  this  the  daily  values  of  the  progressive  rainfall 
indices  are  computed  from  rainfall  records  and  the  flood  control 
feature  applied  just  as  though  the  reservoirs  had  been  operated  through 
these  years  according  to  the  rules  laid  down  by  the  reservoir  operating 
diagrams.  All  conditions  are  held  the  same  in  the  two  parallel  sets  of 
computations  except  for  the  inclusion  of  the  flood  control  feature  in 
one  set. 

Tables  are  included  herein  summarizing  these  computations  and 
comparing  the  yields  of  water  and  power  month  by  month  and  year  by 
year  through  the  entire  period  of  run-off  record.  Graphical  compari- 
sons are  also  included  of  the  reservoir  levels  with  and  without  flood 
control  and  of  the  stream  flow  below  the  dam,  controlled,  as  well  as  that 
unimpaired  by  reservoir  construction. 

Kennett    Reservoir  on   Sacramento    River. 

The  ' '  Coordinated  Plan ' '  *  for  development  of  the  State 's  waters 
presented  to  the  1927  session  of  the  State  Legislature  proposes,  among 
others,  that  a  reservoir  be  constructed  on  the  main  Sacramento  River 
with  its  dam  near  Kennett,  about  five  miles  below  the  confluence  with 
the  Pit  River.  The  plan  proposes  that  the  dam  be  constructed  to  an 
initial  height  of  420  feet.  This  would  impound  2,940,000  acre-feet  of 
water.  A  power  plant  of  400,000  k.  v.  a.  capacity  would  be  constructed 
near  the  base  of  the  dam. 

The  "Coordinated  Plan"  is  distinguished  from  other  plans  in  that 
its  reservoirs  would  be  operated  coordinately  for  several  different 
purposes  in  a  way  to  subserve  the  best  interests  of  the  State.  The 
Kennett  reservoir  would  be  operated  coordinately  for  the  benefit  of 
irrigation  and  domestic  supply,  navigation,  salinity  control,  generation 
of  power  and  the  control  of  floods.  During  the  first  period  of  years 
while  the  demand  for  water  is  growing  to  meet  its  large  yield,  the 
Kennett  reservoir  would  be  operated  to  secure  the  most  valuable  power 
output  while  at  the  same  time  limiting  floods  to  half  the  largest  on 
record.  In  so  doing,  for  a  number  of  years  to  come,  there  would  be 
adequate  water  in  the  discharge  from  the  power  plant  for  the  needs  of 
irrigation,  domestic  supply,  navigation  and  for  salt  water  control  in 
all  except  extremely  dry  years.  Later,  the  increased  demand  for  water 
will  require  that  the  operation  of  the  reservoir  be  changed  over  to  yield 
the  greatest  volume  of  water  equalized  in  accord  with  the  irrigation 
demand  while  at  the  same  time  meeting  the  other  needs.  The  genera- 
tion of  power  would  become  incidental  to  the  yield  of  water.     So 

•  See  Bui.  No.  12,  "Summary  Report  on  the  Water  Resources  of  California  and  a 
Coordinated  Plan  for  their  Development,"  Division  of  Engineering  and  Irrigation, 
State  Department  of  Public  Works. 


100  WATER    RESOURCES    OF    CALIFORNIA. 

operated,  the  initial  ln'iu;lii  oi"  dam  would  e(|ualize  for  irrigation  use 
three-fifths  of  tiie  mean  annual  run-oft"  of  the  stream  and  produce  on 
an  average  35!), 400*  kilowatts  of  electric  energy. 

The  yield  of  the  Kennett  reservoir  in  water  and  power  for  several 
heights  of  dam  together  with  a  full  description  of  its  uses  is  contained 
in  Bulletin  No.  15,  "The  Coordinated  Plan  of  Water  Development  in 
the  Sacramento  Valley."  The  results  of  computations  for  several 
heights  of  dam  are  there  tabulated.  No  special  entries  are  included 
for  navigation  water  nor  for  water  for  salinity  control  since  their  needs 
would  be  more  or  less  coincident  with  the  irrigation  demand.  They 
are  regarded  as  part  of  this  demand  for  estimating  purposes.  Like- 
wise, no  special  entries  are  made  for  domestic  water  supply  because  its 
volume  would  be  relatively  small.  The  effect  of  the  inclusion  of  the 
flood  control  feature  of  the  "Coordinated  Plan"  upon  the  yield  of  a 
reservoir  with  a  420-foot  dam,  the  initial  height  proposed,  is  analyzed 
in  the  following  pages. 

Plate  XXIII,  "Effect  of  Controlling  Sacramento  River  Floods  upon 
Stage  of  Kennett  Reservoir,"  compares  the  reservoir  stage  day  by  day 
had  it  been  in  existence  in  the  year  1895  and  been  operated  continu- 
ously to  January,  1926,  as  proposed  in  the  "Coordinated  Plan,"  with 
the  stage  had  the  flood  control  feature  been  omitted.  This  period  of 
comparison  is  the  extent  of  continuous  records  of  stream  flow  on  the 
Sacramento  River.  The  comparison  is  delineated  by  lines  extending 
across  the  plate  in  four  rows.  Each  line  represents  a  separate  mode  of 
operation.  These  lines  fluctuate  up  and  down  and  indicate  bj'  their 
vertical  position  the  acre-feet  of  water  in  storage  in  the  reservoir  on 
each  day  of  the  thirty-year  period  under  the  several  different  modes  of 
operation.  The  top  guide  line  of  each  row  represents  a  full  reservoir 
and  the  bottom  line  an  empty  reservoir.  The  space  between  each  pair 
of  guide  lines  represents  200,000  acre-feet  of  capacity. 

The  heavy  black  line  extending  across  each  row  indicates  the 
reservoir  stage  had  the  most  valuable  power  output  been  generated  as 
proposed  in  the  first  or  temporary  mode  of  operation  under  the 
"Coordinated  Plan."  A  dash  and  dot  black  line  indicates  the  stage 
had  the  greatest  yield  of  irrigation  water  been  obtained  with  electric 
power  as  an  incidental  product  as  proposed  in  the  second  or  permanent 
mode  of  operation  under  the  "Coordinated  Plan. "  These  lines  approx- 
imate operation  as  proposed  by  the  "Coordinated  Plan"  except  that 
the  flood  control  feature  is  omitted. 

The  reservoir  stage  resulting  from  the  introduction  of  the  flood 
control  feature  is  delineated  by  red  lines.  The  light  red  line  indicates 
the  stage  had  the  reservoir  been  operated  for  flood  control  alone  in 
accordance  with  the  rule  developed  in  the  fore  part  of  this  volume  and 
expressed  on  Plate  XVIII,  "Reservoir  Operating  Diagram  for  Con- 
ti-olling  Floods  on  Sacramento  River."  p.  76. 

The  heavy  full  red  line  indicates  the  departures  in  reservoir  stage 
by  reason  of  the  inclusion  of  the  flood  control  feature  in  the  first  or 
temporary  mode  of  operation  under  the  "Coordinated  Plan."  The 
light  dash  and  dot  red  line  indicates  similarly  the  departures  by  reason 
of  the  inclusion  of  the  flood  control  feature  in  the  second  or  permanent 
mode  of  operation  under  the  "Coordinated  Plan."     Where  the  light 

•  Average  for  the  54-year  period,  1871-1925. 


I902 

HAY  June:       july  aug. 


PLATE  XXIII. 


LEGEND 

ol  alone.  (Mot  shown  where  coincident  with  other  red  re 

incidental  irrigation.    Yield  in  power  output  158,200 
irrigation  draft  1.631X00    ac  ft  per  year  (July  draft  5.80 
feenng  and  Irrigation,  pa^e  63,  for  monthly  distribution 

Jth  Incidental  power.  Yield  in  irrigation  draft  4,276.000  ac  * 
1(  see  8ul.  N?  6.  Division  of  Engineering  and  Irrigation,  pa|e  ( 
Ltput  145,300    Kilowatts  (average)  with  an  installed  cap. 

((incidental  irrigation,  where  affected  by  coordinatio 

Hth  incidental  power,  where  affected  by  coordination  witt 

— )  .UFF    125,000    SEC.  FT, 

bnio  River  near  Red  Bluff,  taken  from  records  of  United  P:?°°  .^^^-  '^^• 

River  near  Red  Bluff,  witti  reservoir  operated  for  irrigation 

-)  and  controlled  (-r-v— ""v) 

minfall  from  July  I  up  to  successive  dates  in  the  season,  to  tj 
Hcords  of  United  States  Weather  Bureau  at  Red  Bluff. 


ENTO  River  Floods 


rilESERVOIR 

IGATION  OR  POWER  DRAFT 


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IF  OPERATED  PRIMARILY  FOR  DTHER  IRRIGATION  OR  POWER  ORftFT 

THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  103 

dash  and  dot  red  line  coincides  with  the  heavy  full  red  line,  both  are 
"'^presented  by  a  heavy  dash  and  dot  red  line. 

Below  the  reservoir  stage  lines  in  each  row  are  drafted  to  a  special 
scale  superimposed  on  the  reservoir  stage  scale,  a  light  black  line 
showing  the  fluctuations  of  the  stream  flow  unimpaired  by  reservoir 
storage  and  a  light  red  line  showing  the  stream  flow  as  controlled  by 
the  second  or  permanent  mode  of  operation  under  the  "Coordinated 
Plan."  Similarly,  a  black  dotted  line  delineates  the  values  of  the 
progressive  rainfall  index  that  were  used  with  the  reservoir  oper- 
ating diagram  (Plate  XVIII)  in  computing  the  stage  of  the  reservoir 
with  the  flood  control  feature  included. 

The  greatest  empty  depth  required  for  flood  control  during  each 
season  is  noted  on  the  graph  in  feet  below  full  reservoir  level.  The 
largest  is  seen  to  be  21  of  the  415  feet  depth  behind  the  dam  when  the 
reservoir  is  full.  This  was  required  during  13  of  the  30  seasons.  In  7 
of  the  seasons  there  was  no  special  lowering  of  the  reservoir  level  for 
f  1  control  since  the  empty  space  by  reason  of  conservation  operations 
was  larger  than  required  for  flood  control.  The  average  amount  of 
depression  was  about  11  feet,  or  2.6  per  cent,  of  the  depth  of  a  full 
reservoir  at  the  dam.  Of  the  entire  elapsed  time  during  the  30  seasons, 
the  reservoir  level  would  have  had  to  be  depressed  especially  for  flood 
control  only  one-sixth  of  the  time  while  operating  primarily  for  power 
generation  and  one-eighth  of  the  time  while  operating  primarily  for 
^'  'igation. 

rhe  effect  of  including  the  flood  control  feature  of  the  ' '  Coordinated 
Plan"  upon  the  reservoir  stage  resulting  from  conservation  operations 
is  seen  to  be  small,  yet  very  substantial  reduction  in  flood  volume  is 
obtained.  The  largest  flood  of  record  occurred  in  February,  1909.  It 
rtached  a  crest  discharge  of  278,000  second-feet.  The  flood  control 
feature  of  the  "Coordinated  Plan"  would  have  limited  this  flood  to  a 
discharge  of  125,000  second-feet.  Likewise  the  floods  of  ten  other 
seasons  of  record  that  exceeded  125,000  second-feet  would  have  been 
limited  to  this  rate  of  discharge. 

The  effect  upon  the  water  and  power  yield  of  the  Kennett  reservoir 
in  securing  this  limitation  to  flood  flows  is  disclosed  by  comparison  of 
parallel  sets  of  computations,  one  with  and  the  other  without  the  flood 
control  feature  of  the  "Coordinated  Plan."  These  computations  of 
yield  were  carried  out  as  described  in  Bulletin  No.  15,  "The  Coordi- 
nated Plan  of  Water  Development  in  the  Sacramento  Valley,"  except 
that  they  were  made  on  a  daily  instead  of  a  monthly  basis.  The  set  of 
computations  with  the  flood  control  feature  included  had  to  be  made 
on  a  daily  basis  because  the  reservoir  operating  diagrams  require  a 
daily  adjustment  of  reservoir  stage  during  the  flood  season.  There- 
fore, in  order  to  make  the  two  sets  of  computations  exactly  comparable, 
both  were  carried  through  the  entire  30  years  on  a  daily  basis.  The 
assumptions  employed  are  listed  on  ])age  216  herein. 

The  water  yield  (without  deduction  for  prior  rights  downstream 
from  the  dam  and  with  deficiencies  in  supply  on  an  average  of  one 
year  in  ten)  computed  on  a  daily  basis  is  identical  with  that  of  Bulletin 
No.  15  computed  on  a  montlily  basis  excej^t  that  tlie  deficiencies  in  per 
cent  of  a  full  supply  are  increased  from  0.1  to  0.3  per  cent  in  three 
out  of  the  five  deficient  seasons.     The  power  yield,  however,  is  about 


104  WATER   RESOURCES   OF    CALIFORNIA. 

3  per  cent  less  when  computed  day  by  day  rather  than  by  monthly 
averages.  It  was  2.3  per  cent  less  when  operating  primarily  for  power 
generation  and  3.7  per  cent  less  when  power  generation  is  incidental  to 
irrigation  use.  This  results  from  the  assumption  in  the  monthly  com- 
putations that  flow  is  available  for  power  generation  as  an  average 
monthly  quantity  instead  of  with  the  large  daily  fluctuations  that  some- 
times occur.  At  times  when  the  reservoir  is  full,  some  of  this  water 
included  in  the  monthly  averages  actually  would  have  passed  over  the 
spillway  instead  of  through  the  turbines.  Therefore,  the  computations 
on  a  monthly  basis  show  somewhat  more  water  running  through  the 
power  turbines  than  actually  could  have  passed  through  them. 

The  stream  flow  data  employed  in  these  computations  are  the  esti- 
mated mean  monthly  discharges  at  the  Kennett  dam  site  with  the 
entire  flow  of  the  Pit  Kiver  above  Bieber  deducted  but  without  deduc- 
tion for  prior  rights  downstream  from  the  dam.  These  are  published 
in  Bulletin  No.  15,  "The  Coordinated  Plan  of  Water  Development  in 
the  Sacramento  Valley."  For  the  purposes  of  computing  the  yield  of 
the  reservoir  on  a  daily  basis,  these  estimated  monthly  means  were 
divided  into  daily  discharges  bearing  the  same  relation  to  the  corre- 
sponding daily  flows  measured  at  the  Red  Bluff  gaging  station  as  the 
estimated  mean  monthly  flows  at  the  Kennett  dam  site  bear  to  the 
corresponding  mean  monthly  flows  measured  at  Red  Bluff. 

Summaries  are  prepared  of  these  computations  comparing  the  water 
and  power  yield  of  the  Kennett  reservoir  in  tlie  "Coordinated  Plan," 
with  and  without  the  flood  control  feature.  Those  by  years  follow 
lierewith  but  those  by  months,  because  of  their  size,  have  been  assem- 
bled in  the  last  chapter  of  this  volume. 

It  may  be  observed  upon  reviewing  these  tables  that  the  inclusion  of 
the  flood  control  feature  of  the  "Coordinated  Plan"  has  practically  no 
effect  upon  the  yield  of  the  Kennett  reservoir  either  in  water  or  power. 
The  water  yield  equalized  for  irrigation  use,  both  with  and  without 
flood  control,  is  identical  either  in  the  temporary  or  permanent  mode 
of  operating  the  reservoir.  The  power  yield  is  0.9  per  cent  less  under 
the  temporary  and  0.2  per  cent  greater  under  the  permanent  mode  of 
operation,  all  in  the  secondary  output.  These  differences  are  very 
small  and  are  discernible  only  because  of  the  minute  comparisons  made 
to  detect  them.  They  are  much  smaller  than  the  error  contained  in 
the  usual  computations  of  power  output  that  are  based  on  monthly 
averages  of  stream  flow. 

The  slightly  less  power  output  under  the  temporary  mode  of  opera- 
tion when  flood  control  is  included,  results  from  the  extra  water  that 
may  be  run  through  the  turbines  while  the  reservoir  level  is  depressed 
for  flood  control,  being  insufGcient  at  times  to  compensate  for  the 
slight  reduction  in  power  head.  The  table  shows  that  this  occurs  at 
times  during  16  of  the  30  years.  In  7  of  the  years  the  extra  water 
available  while  the  reservoir  level  is  depressed  for  flood  control  is 
sufficient  to  develop  a  greater  power  output  with  flood  control  than 
without.  In  the  remaining  7  years  the  reservoir  stage  is  not  affected 
by  the  inclusion  of  the  flood  control  feature  since  the  empty  space,  by 
reason  of  conservation  operations,  is  at  all  times  greater  than  needed 
for  flood  control.  Under  such  circumstances  the  power  yield  with  and 
without  flood  control  is  identical.     The  greatest  difference  in  power 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  105 

yield  witli  and  without  flood  control  in  any  year  of  the  30  analyzed  is 
6.7  per  cent.  This  occurred  in  1900.  The  average  reduction  in  power 
head  by  the  inclusion  of  flood  control  is  2.0  feet. 

Under  the  permanent  mode  of  operating  the  reservoir  the  power 
yield  is  greater  with  flood  control  than  without  because  the  extra 
volume  of  water  that  may  be  run  through  the  turbines  by  reason  of 
the  inclusion  of  the  flood  control  feature  is  more  than  sufficient  to 
compensate  for  the  small  depression  in  head.  The  average  reduction 
in  power  head  that  results  from  the  depression  of  the  reservoir  level 
at  times  for  flood  control  is  0.5  feet. 

An  alternate  rule  for  controlling  floods  by  reservoirs. 

The  rules  for  controlling  floods  by  reservoirs  described  herein,  grade 
with  scientific  nicety  the  flood  control  reserve  in  accord  with  the 
probable  need  for  empty  space  to  detain  excess  flood  water.  They  were 
so  constructed  in  order  that  the  program  of  flood  control  evolved  by 
the  analysis  would  interfere  as  little  as  possible  with  conservation.  It 
appears  that,  under  some  circumstances,  this  nicety  of  gradation  in 
the  amount  of  flood  control  reserve  might  be  neglected  without  par- 
ticular detriment  to  the  reservoir  yields.  By  holding  the  maximum 
empty  space  ever  required,  in  reserve  throughout  each  flood  season 
until  its  close  instead  of  varying  it  during  the  season  with  the  changing 
value  of  the  progressive  rainfall  index,  results  could  be  obtained  at  the 
Kennett  reservoir  not  greatly  difi'erent  from  those  secured  by  the  appli- 
cation of  the  reservoir  operating  diagram. 

It  is  evident  that  such  a  rule  would  interfere  with  conservation  very 
seriously  under  some  circumstances,  especially  with  a  small  reservoir. 
On  the  other  hand,  it  is  surprising  how  well  it  fits  occurrences  on  the 
Sacramento  River  from  1895  to  1926  when  applied  to  the  size  reservoir 
proposed  at  Kennett.  The  total  reservoir  capacity  proposed  at  Kennett 
equals  almost  half  the  mean  seasonal  run-off  and  is  about  six  times  the 
maximum  flood  control  reserve.  In  seasons  of  short  run-off  when  it 
would  seem  that  the  nicety  of  gradation  in  the  flood  control  reserve 
obtained  by  the  operating  diagram  .should  be  particularly  valuable,  it 
is  found  generally  that  conservation  draft  holds  the  reservoir  below 
the  level  of  the  maximum  flood  control  reserve.  At  such  times  flood 
control  by  either  rule  does  not  depress  the  reservoir  level.  Hypotheti- 
cal seasons  might  be  constructed  in  which  this  would  not  be  so,  however, 
the  record  of  stream  flow  shows  that  none  have  occurred  within  the 
last  thirty  years.  Should  they  occur,  control  by  the  reservoir  operating 
diagram  would  interfere  less  with  conservation  than  by  the  alternate 
rule. 

The  water  and  power  yield  of  the  Kennett  reservoir  holding  the 
maximum  flood  control  reserve  (454,000  acre-feet)  empty  throughout 
the  sea.son  (until  April  8th)  was  computed  in  parallel  to' that  without 
flood  control  and  to  that  with  control  by  the  reservoir  operating  dia- 
gram. The  yearly  and  monthly  summaries  of  these  computations  are 
included  with  the  others  in  the  adjoining  tables.  The  reduction  in 
yield  from  that  without  flood  control  is  small.  In  the  temporary  mode 
of  operation  under  the  ''Coordinated  Plan,"  the  irrigation  yield  is 
identical  but  the  primary  power  output  is  reduced  3.5  per  cent.  The 
secondar}'  output,  however,  is  increased  5.6  per  cent  so  that  the  net 


106  WATER   RESOURCES   OF    CALIFORNIA. 

reduction  in  total  power  is  1.0  per  cent.  Under  the  permanent  mode 
of  operation,  the  average  irrigation  yield  is  reduced  0.3  per  cent  because 
of  the  larger  deficiencies  in  seasons  of  short  supply.  In  1923  the 
deficiency  is  increased  by  210,000  acre-feet,  5.0  per  cent  of  the  average 
seasonal  yield.  The  incidental  power*  under  the  permanent  mode  of 
operation  is  reduced  between  1  and  2  per  cent.* 

•  A  fuU  set  of  computations  of  the  incidental  power  yield  while  operating  pri- 
marily for  irrigation  was  not  completed.  However,  it  is  estimated  the  average  power 
head  would  be  reduced  about  7.0  feet  and  20,000  to  40,000  acre-feet  more  water 
would  pass  through  the  turbines. 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  107 


KENNETT   RESERVOIR  ON   SACRAMENTO   RIVER. 

Table  of  Yearly  Summaries  of  Water  and  Power  Yield  Computed  on  a 

Daily   Basis. 

Showing  the  effect  of  iuclusion  of  the  flood  control  feature  of  the 
"Coordinated  Plan."      (See  Chapter  VIII  for 
corresponding  monthly  summaries.) 

Table  1 — Operating  primarily  for  power  generation   with  incidental  irrigation. 
With  and  without  flood  control  by  reservoir  operating  diagram. 

Table  2 — Operating  primarily  for  irrigation   with  incidental  power  generation. 
With  and  without  flood  control  by  reservoir  operating  diagram. 

Table  3 — Operating  primarily  for  irrigation.     Comparison  for  two  methods  of 
flood  control. 

Table  4 — Operating  primarily   for  power  generation   with   incidental  irrigation. 
Comparison  for  two  methods  of  flood  control. 

Table  5 — Summary  of  power  yield.     With  and  without  flood  control  by  either  of 
two   methods. 


108 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  1.     KENNETT  RESER 
WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY 

BOTH 
WITH  AND  WITHOUT  FLOOD  CONTROL 

Yearly  Summary  of  Computations 

(For  corresponding  monthly  sum 

Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Esti- 
mated 
run-off 
at 

Without  flood  control 

Stage  of 

Power  draft 

Average  power 

yield 

Year 

reservoir 

through  turbines  in 

Waste 

Average 

n  kilowatt 

site 

in 

acre-feet 

at 

acre-feet 

Evapora- 

over 

(Load  factor= 

0.75) 

beginning 

of 

year  in 

acre-feet 

tion  in 
acre-feet 

spillway 

in 
acre-feet 

power 

head  in 

feet 

Primary 

Secondary 

•Primary 

Secondary 

Total 

1896 

8,306,000 

2,256,000 

3,205,000 

1,968,000 

78,000 

2,491,000 

400 

113,000 

69,500 

182,500 

1897 

6.052,000 

2,820,000 

3,204,000 

1  662,000 

78,000 

1,671,000 

401 

113,400 

59,100 

172,500 

1898 

3,308,000 

2,257,000 

3,218.000 

21,000 

75,000 

0 

392 

113,400 

700 

114,100 

1899 

5.050,000 

2,221,000 

3,206,000 

990,000 

78,000 

299.000 

400 

113,400 

34.900 

148.300 

1900 

5,720,000 

2,698,000 

3,193,000 

1,537,000 

78,000 

1,081,000 

402 

113,400 

54,200 

167,600 

1901 

5,724,000 

2,529,000 

3,196,000 

1,312,000 

78,000 

1,289,000 

401 

113,400 

46,300 

159,700 

1902 

8,685,000 

2,378,000 

3,201,000 

1,659.000 

78,000 

3.185,000 

400 

113,400 

58.900 

172.300 

1903 

6,848,000 

2,940,000 

3,182,000 

1,632,000 

78,000 

1,990,000 

404 

113,400 

58.200 

171.600 

1904 

10,378,000 

2,906,000 

3,204,000 

2,437,000 

78,000 

5,144,000 

400 

113,000 

85,600 

198,600 

1905 

6,823,000 

2,421,000 

3,201,000 

1,429,000 

78,000 

2,276,000 

400 

113,400 

51,000 

164.400 

1906 

7,981,000 

2,257,000 

3,212,000 

1,807,000 

78,000 

2.673,000 

399 

113,100 

63,900 

177,300 

1907 

8,877,000 

2,468,000 

3,208,000 

1,822,000 

78,000 

3,891,000 

399 

113,-tOO 

64,500 

177,900 

1908 

5,355.000 

2,346,000 

3,202,000 

1,390,000 

78,000 

774,000 

400 

113,000 

49,500 

162,500 

1909 

10,871,000 

2,257,000 

3,203,000 

2,116,000 

78,000 

5,053,000 

400 

113,400 

74.800 

188.200 

1910 

5,801.000 

2.678,000 

3,201,000 

1,478,000 

78,000 

1.465,000 

401 

113,400 

52,300 

165,700 

1911 

6,383,000 

2,257,000 

3,212,000 

1,446,000 

78,000 

1,655,000 

398 

113,400 

51,500 

164,900 

1912 

4,935,000 

2,249,000 

3,211,000 

1,333,000 

78,000 

305,000 

398 

113,000 

46.900 

159,900 

1913 

5,017,000 

2,257,000 

3,201,000 

1,189,000 

78,000 

253,000 

400 

113,400 

42,100 

155,500 

1914 

9,085,000 

2,553,000 

3,211,000 

1,921,000 

78,000 

4,171,000 

399 

113,400 

68,000 

181,400 

1915 

9.454.000 

2,257,000 

3,214,000 

1,853,000 

78,000 

4,094,000 

398 

113,400 

65.500 

178,900 

1916 

7,127,000 

2,472,000 

3,208,000 

1,588,000 

78,000 

2,468,000 

400 

113,000 

56,300 

169,300 

1917 

4,705,000 

2,257.000 

3,215.000 

897.000 

78,000 

515,000 

397 

113,400 

32,000 

145,400 

1918 

3,862,000 

2,257,000 

3,222,000 

462,000 

78,000 

100,000 

396 

1 13,400 

16,300 

129,700 

1919 

5,306,000 

2,257,000 

3,211,000 

905,000 

78,000 

1,185,000 

399 

113.400 

32,400 

145,800 

1920 

4,455,000 

2,184,000 

3,373,000 

269,000 

66,000 

0 

376 

113,000 

9,400 

122,400 

1921 

6,255,000 

2,931,000 

3,199,000 

1,447,000 

78,000 

2,139,000 

400 

113,400 

51,600 

165,000 

1922 

4,504.000 

2.323,000 

3,212,000 

913,000 

78,000 

296,000 

398 

113,400 

32,300 

145,700 

1923 

3,294,000 

2,328,000 

3,223,000 

133,000 

78,000 

0 

398 

113.400 

4,600 

118,000 

1924 

2,431,000 

2,188,000 

3,759,000 

0 

53,000 

0 

339 

1 13,000 

0 

113,000 

1925 

5,420,000 
188,012,000 

807,000 

3,361,000 

337,000 

78,000 

211,000 

381 

113,400 

12.100 

125.500 

Total 

97.101,000 

37,953,000 

2,300,000 

50,674,000 

Average 

6,267.000 

3,230,000 

1,265,000 

77,000 

1.689,000 

395.8 

113,400 

44,800 

158,200 

Total  primiry  powpr  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS. 


109 


VOIR  ON  SACRAMENTO  RIVER. 

FOR  POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


BY  RESERVOIR  OPERATING  DIAGRAM. 

Carried  out  on  a  Daily  Basis. 

mary,  see  Table  la,  page  218.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.P.  =  0.80. 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  coDtrolled  flow  at  Red  Bluff  1 25,000  sec.-ft.  Maximum  reservoir  space  required  454,000  ac.-ft. 

Stage  of 
reservoir 

at 
beginning 

Power  draft 

through  turbines  in 

acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 
over 

spillway 
in 

acre-feet 

Average 

power 

head  in 

feet 

Average  power  yield 

in  kilowatts 
(Load  factor=0.75) 

Year 

of 
year  in 
acre-feet 

Primary 

Secondary 

*Priinary 

Secondary 

Total 

2,256,000 
2,595,000 
2,257,000 
2,221,000 
2,588,000 
2,529,000 
2,378,000 
2,652,000 
2,601,000 
2,421,000 
2,257,000 
2,468,000 
2,346,000 
2,257,000 
2.637,000 
2,257,000 
2,249,000 
2,257.000 
2,553,000 
2,257,000 
2.472.000 
2.257.000 
2,257.000 
2,257.000 
2,184,000 
2,727,000 
2,323,000 
2,328,000 
2,188,000 
807,000 

3,225,000 
3,227,000 
3,248,000 
3,209,000 
3,214,000 
3,221,000 
3.214,000 
3,210.000 
3,238.000 
3,217,000 
3,224,000 
3,230,000 
3.226,000 
3,217,000 
3.210.000 
3.228.000 
3.211,000 
3,216,000 
3,221,000 
3,224,000 
3,236,000 
3,220,000 
3,222.000 
3.223,000 
3,374.000 
3.218.000 
3,215,000 
3.223,000 
3,759.000 
3,361,000 

1.701,000 

1,552,000 

21,000 

994,000 

1,238.000 

1.174.000 

1.569.000 

1.647.000 

2,449,000 

1.504,000 

1,849,000 

2,042,000 

1,146,000 

2,099,000 

1,443,000 

1,443,000 

1.333.000 

1,093.000 

1.914.000 

1.964.000 

1,704.000 

770.000 

462.000 

1,020,000 

270.000 

1,391,000 

832.000 

133,000 

0 

337,000 

78,000 
78,000 
75.000 
78.000 
78,000 
78,000 
78,000 
78.000 
78,000 
78,000 
78,000 
78  000 
78,000 
78,000 
78,000 
78,000 
78,000 
78,000 
78.000 
78.000 
78.000 
78.000 
78.000 
78,000 
66,000 
78,000 
78.000 
78.000 
53,000 
78,000 

1,640,000 

1,175,000 

0 

388,000 
1,228,000 
1,402,000 
2,936,000 
1,834  000 
3.592.000 
1,903.000 
1.780,000 
3,044,000 

930,000 

4,785,000 

1,036.000 

1,217,000 

0 

137,000 
3,358,000 
2,509,000 
2,149,000 

178,000 
0 

919,000 

202,000 
1,936.000 

136,000 
0 
0 
0 

1,323,000 

358,000 

0 

14,000 

21,000 

0 

614.000 

130,000 

1,201,000 

285,000 

839,000 

605.000 

64.000 

312.000 

414,000 

425,000 

305,000 

197,000 

810,000 

1,464,000 

175,000 

459,000 

100,000 

139,000 

0 

36,000 

238,000 

0 

0 

211,000 

398 
396 
392 
399 
398 
397 
398 
399 
395 
397 
397 
395 
398 
397 
399 
396 
398 
398 
397 
396 
396 
397 
396 
396 
375 
397 
398 
398 
339 
381 

113,000 
113,400 
113,400 
113,400 
113,400 
113,400 
113,400 
113  400 
113,000 
113,400 
113,400 
113,400 
113,000 
113,400 
113,400 
113.400 
113,000 
113,400 
113,400 
113,400 
113,000 
113,400 
113,400 
113,400 
113,000 
113,400 
113,400 
113,400 
113,000 
113,400 

59,700 
54,300 
700 
35,000 
42,900 
40,400 
55,300 
57,800 
85.100 
53.100 
65.100 
71,400 
40,200 
73,600 
50,800 
50,800 
46,900 
38,500 
67,400 
69,000 
59,500 
27,400 
16,300 
36,000 

9,400 
48,900 
29,400 

4,600 

0 

12,100 

172,700 
167,700 
114,100 
148,400 
156,300 
153,800 
168,700 
171,200 
198,100 
166,500 
178,500 
184,800 
153,200 
187,000 
164,200 
164,200 
159,900 
151,900 
180,800 
182,400 
172,500 
140,800 
129.700 
149,400 
122,400 
162,300 
142,800 
118,000 
113.000 
125,500 

1896 
1897 
1898 
1899 
1900 
1901 
1902 
1903 
1904 
1905 
1906 
1907 
1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 

97,481,000 
3,249.000 

37,094.000 
1,236.000 

2,300,000 
77,000 

40,414,000 
1,347,000 

10,739,000 
358,000 

393.8 

113,400 

43,400 

156,800 

Total 
Average 

110 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  2.     KENNETT  RESER 
WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY 

BOTH 
WITH  AND  WITHOUT  FLOOD  CONTROL 


Yearly  Summary  of  Computations 

(For  corresponding  monthly  sum 


Height  of  dam  420  feet. 

Capacity  of  reservoir  2,940,000  acre-feet. 


, 

Without  flood  control 

Irrigation 

Estimated 

Stage  of 

drjftin 

Power 

draft 

througli 

turbines 

Deficiency 

Average 

Average 

Year 

run-off 

reservoir 

acre-feet 

Waste 

power 

power 

at  dam 

at 

(no 

Evapora- 

over 

in 

head 

yield  in 

site  in 

beginning 

deduction 

tion  in 

spillway 

irrigation 
supply 

through 

kilowatts 

acre-feet 

of 

for  down- 

acre-feet 

in 

period  of 

(Load 

year  in 
acre-feet 

stream 
prior 
rigiits) 

in 
acre-feet 

acre-feet 

in 
acre-feet 

operation 
in  feet 

factor^ 
1.00) 

1896 

8,306,000 

1,860,000 

4,276,000 

65,000 

5,286,000 

1,678.000 

0 

375 

178,400 

1807 

6,052,000 

2,586,000 

4,276,000 

59,000 

5,531,000 

1,172,000 

0 

359 

180,800 

1898 

3,308,000 

1,408,000 

4,189,000 

43,000 

3,149,000 

0 

87,000 

342 

91,200 

1899 

5,050,000 

484,000 

4,123,000 

39,000 

3,130,000 

0 

153,000 

329 

88,700 

1900 

5,720,000 

1,372,000 

4,276,000 

55,000 

4,723,000 

327,000 

0 

337 

145,500 

1901 

5,724,000 

1,534,000 

4,276,000 

54,000 

4,721,000 

759,000 

0 

336 

144.900 

1902 

8,685,000 

1,268,000 

4,276,000 

61,000 

5,051,000 

1,919,000 

0 

361 

166.300 

1903 

6,848,000 

2,432,000 

4,276,000 

54,000 

5.545,000 

1,350,000 

0 

347 

176,700 

1904 

10.378,000 

1,872.000 

4.276,000 

65,000 

5,055  000 

4,108,000 

0 

372 

170,200 

1905 

6,823,000 

2,462,000 

4,276,000 

59,000 

5,727,000 

1.822,000 

0 

361 

188,300 

1906 

7,981,000 

1,206,000 

4,276,000 

69,000 

4,713,000 

1,491,000 

0 

378 

161,500 

1907 

8,877,000 

2,309,000 

4.276,000 

65,000 

5,553,000 

3,257,000 

0 

369 

186,200 

1908 

5,355,000 

1,795,000 

4,276,000 

58,000 

5,170.000 

302,000 

0 

353 

166,000 

1909 

10,871,000 

1,155,000 

4,276.000 

59,000 

5,723,000 

3,543,000 

0 

362 

190,400 

1910 

5,801,000 

2,216,000 

4,276,000 

55,000 

5,383,000 

911,000 

0 

347 

171,100 

1911 

6,383,000 

1,215,000 

4,276,000 

63,000 

4,709,000 

868,000 

0 

362 

155,500 

1912 

4,935,000 

1,447,000 

4.276,000 

61,000 

4,032,000 

83,000 

0 

360 

130,200 

1913 

5,017,000 

1,709,000 

4,276,000 

58,000 

4,537,000 

58,000 

0 

348 

143,800 

1914 

9,085,000 

1.611,000 

4,276.000 

65,000 

5.729.000 

2,744,000 

0 

370 

192,800 

1915 

9,454,000 

1.631,000 

4,276,000 

66,000 

5,341,000 

2,972,000 

0 

374 

181.100 

1916 

7,127,000 

2,138,000 

4,276.000 

59.000 

5.627,000 

1,798,000 

0 

358 

183.300 

•,917 

4,705,000 

1,321,000 

4.276.000 

59,000 

4,124,000 

236.000 

0 

348 

129.700 

1918 

3,862,000 

1.132,000 

4.276,000 

50,000 

3,158,000 

0 

0 

354 

96.400 

1919 

5,306,000 

668,000 

4,276,000 

54,000 

1,533,000 

215,000 

0 

334 

138.500 

1920 

4,455,000 

719,000 

3.121,000 

24.000 

1.970.000 

0 

1,155,000 

315 

53,400 

1921 

6,255,000 

2,029,000 

4.276.000 

56,000 

5.514,000 

1,186,000 

0 

350 

176,800 

1922 

4.504,000 

1.059.000 

4.276.000 

56.000 

3,801,000 

0 

0 

342 

116.700 

1923 

3,294,000 

1,426.000 

4.101.000 

43,000 

3,134,000 

0 

175,000 

341 

91.100 

1924 

2,431,000 

376.000 

2,136,000 

13,000 

1,072,000 

0 

2,140,000 

283 

25.600 

1925 

5,420,000 

658.000 

4,276,000 

54,000 

4,353,000 

297,000 

0 

352 

135.500 

Total 

188,012.000 

124,570.000 

1,641,000 

136,102,000 

33.096,000 

3,710,000 

Average 

6,267,000 

4,152,000 

55,000 

4,.537.000 

1,103,000 

124.000 

353. 4 

145,300 

THE  CONTROL  OF  FLOODS  BY  RESERVOmS. 


Ill 


VOIR  ON  SACRAMENTO  RIVER. 

FOR  IRRIGATION  WITH  INCIDENTAL  POWER  GENERATION 


BY  RESERVOIR  OPERATING  DIAGRAM. 

Carried  out  on  a  Daily  Basis. 

mary,  see  Table  2a,  page  234.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 

Installed  capacity  of  power  plant  400,000  k.v.a.     P.P.  =  0.80. 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

1 

Maximum  controUed  flow  at  Red  Bluff  125,000  sec.-f  t.  Maximum  reservoir  space  re 

quired  454,000  ac.-ft. 

Irrigation 

Stage  of 
reservoir 

at 
l)eginning 

of 
year  in 
acre-feet 

draft  in 
acre-feet 

(no 
deduction 
for  down- 
stream 
prior 
rights) 

Evapora- 
tion in 
acre-feet 

Power 

draft 

through 

turbines 

in 
acre-feet 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

irrigation 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period  of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor— 
1.00) 

Year 

1,860,000 

4,276.000 

65,000 

4,901,000 

1,148.000 

915,000 

0 

373 

164,000 

1896 

2,586,000 

4,276,000 

59,000 

5,616,000 

916,000 

171,000 

0 

358 

181,900 

1897 

1.408,000 

4,189,000 

43,000 

3,149,000 

0 

0 

87,000 

342 

91,200 

1898 

484,000 

4,123,000 

39,000 

3,130.000 

0 

0 

153,000 

329 

88,700 

1899 

1.372,000 

4,276,000 

55,000 

4,745,000 

305,000 

0 

0 

342 

145,300 

1900 

1.534,000 

4,276,000 

54,000 

4,670,000         810,000 

0 

0 

337 

142,000 

1901 

1,268,000 

4,276,000 

61,000 

4,949,000 

1,682,000 

339,000 

0 

359 

161,600 

1902 

2,432,000 

4,276,000 

54,000 

5,722,000 

1,149,000 

24,000 

0 

345 

181,000 

1903 

1,872,000 

4.276,000 

65,000 

5,152,000 

3.170,000 

841,000 

0 

370 

172.600 

1904 

2,462,000 

4.276,000 

59,000 

5,908,000 

1,550,000 

91,000 

0 

359 

193,300 

1905 

1,206,000 

4,276,000 

69,000 

4,798,000 

1.100,000 

.306.000 

0 

377 

163,700 

1906 

2,309,000 

4.276,000 

65,000  j  5,989,000 

2.468.000 

352,000 

0 

366 

199,700 

1907 

1,795,000 

4,276,000 

58,000      4,919,000 

553,000 

0 

0 

352 

155,900 

1908 

1,155,000 

4,276,000 

59,000  :  5,648,000   ,  3,524.000 

94.000 

0 

363 

186,400 

1909 

2.216,000 

4.276.000 

55,000 

5,369,000 

708.000 

217,000 

0 

347 

170,100 

1910 

1,215,000 

4,276.000 

63.000 

4,952,000 

481,000 

144,000 

0 

363 

163.400 

1911 

1,447,000 

4,276,000 

61,000 

4,032,000 

0 

83,000 

0 

360 

130,200 

1912 

1,709,000 

4.276.000 

58,000 

4,533.000  1        10.000 

5-',0;i0 

0 

352 

143.600 

1913 

1,611,000 

4.276,000 

65,000 

5,761,000 

2,214,000 

498,000 

0 

369 

192,900 

1914 

1,631,000 

4,276,000 

66,000 

5,390,000 

1,896,000 

1,027,000 

0 

372 

181,900 

1915 

2,138,000 

4,276,000 

59,000 

5.790,000 

1,598,000 

37,000 

0 

355 

187,200 

1916 

1,321,000 

4.276.000 

59,000 

4,124,000 

0 

235,000 

0 

348 

129,700 

1917 

1.132,000 

4,276,000 

50,000 

3,158,000 

0 

0 

0 

354 

96,400 

1918 

668,000 

4,276,000 

54,000 

4,665,000 

48,000 

35,000 

0 

332 

142,900 

1919 

719,000  i  3.121,000 

24,000 

1,979.000  ;           0 

0 

1,155,000 

315 

53,400 

1920 

2,029,000 

4,276,000 

56,000 

5,608,000 

1,092,000 

0 

0 

348 

178,700 

1921 

1,0.59,000 

4,276.000 

56,000 

3,801,000 

0 

0 

0 

342 

116,700 

1922 

1.226,000 

4,101,000 

43,000 

3,134.000 

0 

0 

175,000 

341 

91,100 

1923 

376,000 

2,136,000 

13,000 

1,072,000 

0 

0 

2,140,000 

283 

25.600 

1924 

658,000 

4,276,000 

54,000 

4.318,000 

152,000 

180.000 

0 

1         352 

133,900 

1925 

124,570,000 

1,641,000    136,982,000    26,574,000 

5,642,000 

3,710.000 

1 

Total 

4,152,000 

55,000      4,566,000  1      886,000 

188,000 

124,000 

352.9 

[ 

145,600 

Average 

112 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  3.     KENNETT  RESER 
COMPARISON  OF  WATER  YIELD 

FOR 
TWO  METHODS  OF 

Yearly  Summary  of  Computations 

(For  corresponding  monthly  sum 


Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Flood  control  by  reservoir  operating  diagram 

Maximum 

controlled  flow  at  Red  Bluff  125.000  sec.-ft. 

Estimated 

nin-off  at 

dam  site  in 

acre-feet 

Maximum  reservoir  space  required  454,000  ac.-ft. 

Year 

Stage  of 
reservoir  at 
beginning 
of  year  in 

acre-feet 

Irrigation 

draft  in 

acre-feet 

(no  deduction 

for  downstrean 

Evaporation 
in  acre-feet 

Release 

through  flood 

control  outlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficienc}' 

in  irrigation 

supply  in 

acre-feet 

prior  rights) 

1896 

8,306,000 

1,860,000 

4,276.000 

65,000 

1,767,000 

1,472,000 

0 

1897 

6,052.000 

2,586,000 

4.276,000 

59,000 

2,413,000 

482,000 

0 

1898 

3,308,000 

1.408.000 

4.189.000 

43,000 

0 

0 

87,000 

1899 

5,050.000 

484.000 

4.123.000 

39,000 

0 

0 

153.000 

1900 

5,720,000 

1,372.000 

4,276,000 

55,000 

1,053,000 

174,000 

0 

1901 

5,724,000 

1.534.000 

4.276,000 

54.000 

1,635,000 

25.000 

0 

1902 

8,685,000 

1,268,000 

4,276,000 

61,000 

2,507,000 

677.000 

0 

1903 

6,848,000 

2,432,000 

4,276,000 

54,000 

2,773.000 

305.000 

0 

1904 

10,378,000 

1,872,000 

4,276,000 

65,000 

4,264,000 

1.183,000 

0 

1905 

6.823,000 

2,462,000 

4,276,000 

59.000 

3,278,000 

466,000 

0 

1906 

7.981,000 

1,206,000 

4,276,000 

69,000 

1.887,000 

616,000 

0 

1907 

8,877.000 

2.309.000 

4,276.000 

65,000 

4.385.000 

665,000 

0 

1908 

5,355,000 

1.795.000 

4,276,000 

58,000 

1.401.000 

260.000 

0 

1909 

10,871,000 

1,155.000 

4,276,000 

59,000 

5,001.000 

474,000 

0 

1910 

5,801.000 

2,216,000 

4,276,000 

55,000 

1,586,000 

885,000 

0 

1911 

6,383,000 

1,215,000 

4,276,000 

63,000 

1,357,000 

455,000 

0 

1912 

4,935,000 

1,447,000 

4.276.000 

61.000 

0 

336,000 

0 

1913 

5,017,000 

1,709,000 

4,276,000 

58.000 

172,000 

609,000 

0 

1914 

9,085,000 

1,611.000 

4,276,000 

65.000 

3,843,000 

881.000 

0 

1915 

9,454,000 

1.631.000 

4,276,000 

66,000 

3,165.000 

1,440,000 

0 

1916 

7.127,000 

2.138.000 

4,276,000 

59,000 

3,223,000 

386.000 

0 

1917 

4.705  000 

1.321,000 

4,276,000 

59,000 

0 

559.000 

0 

1918 

3,862,000 

1.132.000 

4,276,000 

50,000 

0 

0 

0 

1919 

5.306.000 

668,000 

4,276,000 

54.000 

591,000 

334,000 

0 

1920 

4,455,000 

719,000 

3,121,000 

24,000 

0 

0 

1.155.000 

1921 

6,255.000 

2,029,000 

4,276,000 

56,000 

2,682,000 

211.000 

0 

1922 

4,504,000 

1,059,000 

4.276,000 

56,000 

0 

5.000 

0 

1923 

3,294.000 

1,226.000 

4,101,000 

43,000 

0 

0 

175,000 

1924 

2431.000 

376,000 

2,136,000 

13,000 

0 

0 

2,140.000 

1925 

5.420,000 

658,000 

4,276,000 

54,000 

526,000 

487.000 

0 

Total 

188,012,000 

124,570,000 

1,641,000 

49,509,000 

13.417.000 

3,710,000 

Average 

6,267,000 

4,152,000 

55,000 

1,650,000 

•147,000 

124,000 

THE  CONTROL  OF  FLOODS  BY  RESERVOIRS. 


113 


VOIR  ON  SACRAMENTO  RIVER. 
OPERATING  PRIMARILY  FOR  IRRIGATION 


FLOOD  CONTROL. 

Carried  out  on  a  Daily  Basis. 

mary,  see  Table  3a,  page  250.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 


Flood  control,  holding  maximum  reservoir  space  required  (454,000  ac.-ft.)  in  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Stage  of 
reservoir  at 
beginning 
of  year  in 
acre-feet 

Irrigation 
draft  in 
acre-feet 

Evaporation 

Release 
through  flood 

Waste  over 

spillway  in 

acre-feet 

Deficiency 
in  irrigition 

Year 

(no  deduction 

for  downstream 

prior  rights) 

in  acre-feet 

control  outlets 
in  acre-feet 

supply  in 
acre-feet 

1,860,000 

4,276,000 

65,000 

2,760,000 

579,000 

0 

1896 

2,486,000 

4,276,000 

59,000 

2,747,000 

48,000 

0 

1897 

1.408,000 

4,184,000 

43,000 

5,000 

0 

92,000 

1898 

484.000 

4,123,000 

39,000 

0 

0 

153,000 

1899 

1,372,000 

4,276,000 

47,000 

1,506,000 

0 

0 

1900 

1,263,000 

•  4,268,000 

44,000 

1,727,000 

0 

8,000 

1901 

948,000 

4,276,000 

61,000 

2,705,000 

159,000 

0 

1902 

2,432.000 

4,276,000 

53,000 

3,206,000 

0 

0 

1903 

1,745,000 

4,270,000 

65,000 

4,634,000 

686,000 

0 

1904 

2,462,000 

4,276,000 

57,000 

3,862,000 

0 

0 

1905 

1,090,000 

4,276,000 

69,000 

2,253,000 

164,000 

0 

1906 

2,309,000 

4,276,000 

65,000 

4,792,000 

258,000 

0 

1907 

1,795.000 

4.276,000 

54,000 

1.867,000 

0 

0 

1908 

953,000 

4,276,000 

59,000 

5,331.000 

0 

0 

1909 

2.158,000 

4,276,000 

53,000 

2,556,000 

0 

0 

1910 

1,074,000 

4,276,000 

63,000 

1,634,000 

37,000 

0 

1911 

1,447,000 

4,276,000 

59,000 

511,000 

0 

0 

1912 

1,536,000 

4,276,000 

55,000 

734,000 

0 

0 

1913 

1,488,000 

4,276,000 

65,000 

4,337,000 

264.000 

0 

1914 

1.631.000 

4,276,000 

66,000 

3,894,000 

711,000 

0 

1915 

2,138,000 

4,276,000 

55,000 

3,735,000 

0 

0 

1916 

1,199,000 

4,276,000 

59,000 

323,000 

114,000 

0 

1917 

1,132  000 

4,248,000 

45,000 

110.000 

0 

28,000 

1918 

591,000 

4,276,000 

51,000 

948,000 

0 

0 

1919 

622,000 

3,026,000 

22,000 

0 

0 

1,250,000 

1920 

2,029,000 

4,276,000 

51,000 

3,119,000 

0 

0 

1921 

838,000 

4,276,000 

53,000 

2.000 

0 

0 

1922 

1,011,000 

3,891,000 

38,000 

0 

0 

385,000 

1923 

376,000 

2,136.000 

13,000 

0 

0 

2,140,000 

1924 

658,000 

4,276,000 

54,000 

959,000 

54,000 

0 

1925 

124,224,000 

1,582,000 

60.257,000 

3,074.000 

4,056,000 

Total 

4,141,000 

53,000 

2,009,000 

102,000 

135,000 

Average 

114 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  4.     KENNETT  RESER 
COMPARISON  OF  WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY 

TWO  METHODS  OF 

Yearly  Summary  of  Computations 

(For  corresponding  monthly  sum 

Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  12r,000  sec 

.-ft. 

Esti- 

Maximum reserve  space  required  454,000  ac.-ft. 

mated 
run-off 

Year 

at 

Stage  of 

Power  draft 

Release 

Average  power 

yield 

dam 

reservoir 

through  turbines  in 

through 

Waste 

Average 

in 

kilowatts 

site 

at 

acre-feet 

Evapora- 

flood 

over 

(Load  factor=0.75) 

in 
acre-feet 

beginning 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

of 

year  in 
acre-feet 

Primary 

S;cond- 
ary 

in 
acre-feet 

acre-feet 

•Primary 

.Second- 
ary 

Total 

1896 

8,306,000   2,256,000 

3,225,000 

1,701,000 

78,000 

1,640,0001  1,323,000 

398 

113,000 

59,700 

172,700 

1897 

6,052,000   2,595,000 

3,227,000 

1,552,000 

78,0001  1,175,0001     358,000 

396 

113,400 

54,300 

167,700 

1898 

3,308,000   2.257,000  3,248.000 

21.000 

75.000:              0'               0 

392 

113,400 

700 

114,100 

1899 

5,050.000,  2,221.000  3,209,000 

994.000 

78,0001     388,000!       14.000       399 

113,400 

35,000 

148,400 

1900 

5,720,000   2,088,000!  .3,214.000 

1,238,000 

78,0001  1.228.000!       21,0001      398 

113,400 

42,900 

156,300 

1901 

5,724,000   2,529,000  3.221,000 

1,174,000 

78.000  1,402,0001               0       397 

113,400 

40,400 

1.53,800 

1902 

8.685,0001  2,378.0001  3,214,000 

1,569,000 

78.000J  2,936,0001     614,000|      398 

113,400 

55,300 

168.700 

1903 

6,848,000,  2,652.000!  3.210.000 

1,647,000 

78,000   1. 834.0001     130,000!      399 

113,400 

57,800 

171,200 

1904 

10,378,000    2,601,000'  3.238,000 

2,449,000 

78,000;  3,592,090   1,201,000|      395 

113,000 

85,100 

198.100 

1905 

8,823,000    2,421,000  3,217,000 

1,504,000 

78,000  1,903,000,     285,000 

397 

113,400 

53,100 

166,500 

1906 

7,981,000   2,257,000 

3,224,000 

1,849,000 

78,000l  1,780,000!     839,000 

397 

113,400 

65,100 

178,500 

1907 

8,877,000   2,468,000 

3,230,000 

2,042,000 

78,000  3,044,0001     605,000 

395 

113.400 

71,400 

184.800 

1908 

5,355,000!  2,346,000 

3,226,000 

1.146,000 

78,000      930,000 

64,000 

398 

113,000 

40,200 

153,200 

1909 

10,871,000   2,257,000 

3,217,000 

2,099,000 

78.000  4.785.000 

312,000 

397 

113,400 

73.600 

187,000 

1910 

5,801,000   2,637,000 

3,210,000 

1,443.000 

78.000!  1.036.000 

414,000 

399 

113,400 

50.800 

164.200 

1911 

6,383,000   2,257,000 

3.228,000 

1,443,000 

78.0001  1,217,000 

425,000 

396 

113,400 

50,800 

164.200 

1912 

4,935,000   2,249,000 

3,211,000 

1.333.000 

78.000;               0 

305,000 

398 

113,000 

40,900 

15,1.900 

1913 

5,017,000'  2,257,000 

3,216,000 

1.093,000 

78.000!     137,000 

197,000 

398 

113,400 

38,500 

151.900 

1914 

9,085,000;  2,553,000 

3,221,000 

1,914,000 

78,000!  3,358,000 

810,000 

397 

113,400 

67,400 

180.800 

1915 

9,454,000,  2,257,000 

3,224,000 

1,964,000 

78,000 

2,509,0001  1,464.000 

396 

113,400 

69,000 

182.400 

1916 

7,127,000'  2,472.000 

3,236,000 

1,704,000 

78,000 

2,149,900 

175,000 

396 

113,000 

59,500 

172,500 

1917 

4,705,000!  2,257,000 

3,220,000 

770,000 

78,000 

178,000 

459,000 

397 

113,400 

27,400 

140,800 

1918 

3,862,000    2.257,000 

3,222,000 

462,000 

78,000 

0 

100,000 

396 

113,400 

16,300 

129,700 

1919 

5,306,000   2,257,000 

3,223,000 

1,020,000 

78,000 

919,000 

139,000 

396 

113,400 

36,000 

149,400 

1920 

4,455,000   2.184,000 

3.374.000 

270,000 

66,000 

202,000 

0 

375 

113,000 

9,400 

122,400 

1921 

6,255,000:  2,727,000 

3.218,000 

1,391,000 

78.000 

1,936,000 

36.000 

397 

113,400 

48,900 

162,300 

1922 

4,504,000:  2,323,000 

3,215,000 

832,000 

78,000 

136,000 

238,000 

398 

113,400 

29,400 

142,800 

1923 

3,294,000,  2,328,000 

3,223,000 

133,000 

78,000 

0 

0 

398 

113,400 

4,600 

118,000 

1924 

2,431,000   2,188,000 

3,759,000 

0 

53,000                0 

0 

339 

113,000 

0 

113,000 

1925 

5,420,000,     807.000|  3,361,000 

337,000 

78.000                0 

211.000 

381 

113,400 

12.100 

125.500 

Total 

188,012.000                  97,481,000 

37,094,000 

2.300,000'40.414,000 

10,739,000 

Average 

6.267,000                   3.249,000 

1,238,000 

77,000  1,347,000 

358,000 

393.8 

113.400 

43.400 

156,800 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS. 


115 


VOIR  ON  SACRAMENTO  RIVER. 

FOR  POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION  FOR 

FLOOD  CONTROL. 

Carried  out  on  a  Daily  Basis. 

many,  see  Table  4a,  page  26b.) 

Installed  capacity  of  power  plant  400,000  k.v.a.     P.F.  =  0.80. 


Flood  control,  holding  maximum  reservoir  space  required  (454,000  ac.-ft.)  In  reserve 

throughout  flood  season 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Stage  of 

Power  draft 

Release 

Average  power  yield 

Year 

reservoir 

through  turbines  in 

through 

Waste 

Average 

in  kilowatts 

at 

acre-feet 

Evapora- 

flood 

over 

(Load  factor^ 

=0.75) 

beginning 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

of 

year  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-feet 

*Primary 

Second- 
ary 

Total 

2,075,000 

3,149,000 

2,102,000 

76,000 

1,800,000 

768,000 

392 

109,100 

73,000 

182,100 

1896 

2,486,000 

3,149,000 

1,933,000 

75,000 

1,306,000 

0 

391 

109,400 

67,100 

176,500 

1897 

2,075,000 

3,190,000 

46,000 

72,000 

0 

0 

384 

109,400 

1,500 

110,900 

1898 

2,075,000 

3,149,000 

887,000 

73,000 

541,000 

0 

390 

109,400 

30,400 

139,800 

1899 

2,475,000 

3,146,000 

1,373,000 

74,000 

1,222,000 

0 

391 

109,400 

47,100 

156,500 

1900 

2,380.000 

3,154,000 

1,270,000 

73,000 

1,356,000 

0 

389 

109,400 

43,400 

152,800 

1901 

2,251,000 

3,143,000 

1,853,000 

75,000 

3,194,000 

185,000 

391 

109,400 

64,500 

173,900 

1902 

2,486,000 

3,140,000 

1,567,000 

74,000 

2.089,000 

0 

392 

109,400 

54,100 

163,500 

1903 

2,464,000 

3,155,000 

2,679,000 

77,000 

3,930,000 

764,000 

391 

109,100 

92.300 

201,400 

1904 

2,237.000 

3,157,000 

1,525,000 

74,000 

2,229,000 

0 

390 

109,400 

52,800 

162,200 

1905 

2,075,000 

3,144,000 

2,131,000 

77,000 

1,914.000 

465,000 

391 

109,400 

74,100 

183,500 

1906 

2,325,000 

3,147,000 

2,264,000 

76,000 

3,307,000 

233,000 

391 

109,400 

78,500 

187,900 

1907 

2,175,000 

3,164,000 

1,339,000 

74,000 

878,000 

0 

390 

109,100 

46,200 

155,300 

1908 

2,075,000 

3,153,000 

2,202,000 

75,000 

5,055,000 

0 

390 

109,400 

76,100 

185,500 

1909 

2,461,000 

3,151,000 

1,575,000 

74,000 

1,387,000 

0 

390 

109,400 

54,100 

163,500 

1910 

2,075,000 

3,157,000 

1,699,000 

75,000 

1,378,000 

74,000 

390 

109,400 

59,300 

168,700 

1911 

2,075,000 

3,161,000 

1,577,000 

75,000 

120,000 

0 

390 

109,100 

54,500 

163,600 

1912 

2,077,000 

3,152,000 

1.388,000 

74,000 

91,000 

0 

390 

109,400 

48,000 

157,400 

1913 

2,389.000 

3,147,000 

2,209,000 

76,000 

3,695,000 

272,000 

390 

109,400 

76,500 

185,900 

1914 

2,075,000 

3,147,000 

2,087,000 

76,000 

3,042,000 

834,000 

391 

109,400 

72,400 

181,800 

1915 

2,343,000 

3,164,000 

1,695,000 

74,000 

2,462,000 

0 

389 

109,100 

58,300 

167,400 

1910 

2,075,000 

3,158,000 

1,188,000 

75,000 

227,000 

57,000 

389 

109,400 

41,700 

151,100 

1917 

2,075,000 

3,168,000 

409,000 

74,900 

211,000 

0 

387 

109,400 

14,000 

123,400 

1918 

2,075,000 

3,156,000 

835,000 

74,000 

1,245,000 

0 

389 

109,400 

29,000 

138,400 

1919 

2,071,000 

3,290,000 

192,000 

66,000 

492,000 

0 

371 

109,100 

6,500 

115,600 

1920 

2,486,000 

3,154,000 

1,309,000 

74,000 

2,043,000 

0 

390 

109,400 

45,100 

154,500 

1921 

2,161,000 

3,1,59,000 

981,000 

74,000 

296,000 

0 

389 

109,400 

33,900 

143,300 

1922 

2,155,000 

3,152,000 

71,000 

74,000 

77,000 

0 

390 

109,400 

2,500 

111,900 

1923 

2,075,000 

3,692,000 

0 

53,000 

0 

0 

334 

109,100 

0 

109,100 

1924 

761,000 

3,290,000 

594,000 

75,000 

147,000 

0 

375 

109,400 

20,900 

130,300 

1925 

95,438,000 

40,980,000 

2,208,000 

45,734,000 

3,652,000 

Total 

3,181,000 

1,366,000 

74,000 

1,524,000 

122,000 

386.9 

109,400 

47,300 

156,700 

Average 

116 


WATER   RESOURCES   OP    CALIFORNIA. 


TABLE  5.     KENNETT  RESER 

SUMMARY  OF  POWER 

BOTH 

WITH  AND  WITHOUT 

Summary  of  Tables 

(For  corresponding  monthly  sum 

Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Operating  primarily  for  power  generation  with  incidental  irrigation 

Average  power  yield  in  kilowatts  (Load  factor^O.75) 

Year 

Without  flood  control 

Coordinated  with  flood  control 

by  reservoir  operating  diagram 

Maximum  controlled  flow 

at  Red  Bluff  125,000  sec.-ft. 

Maximum  reservoir  space 

required  454.000  acre-feet 

With  flood  control,  holding 

maximum  reservoir  space 

required  (454,000  ac.-ft.)  in 

reserve  throughout  flood  season 

Maximum  controlled  flow 

at  Red  Bluff  125,000  sec.-ft 

•Primary 

Secondary 

Total 

•Primary 

Secondary 

Total 

•Primary 

Secondary 

Total 

1896 
1897 
1898 
1899 
1900 
1901 
1902 
1903 
1904 
1905 
1906 
1907 
1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 

1 13.000 
113,400 
113,400 
113,400 
113.400 
113.400 
113.400 
113,400 
113,000 
113,400 
113,400 
113.400 
113,000 
113,400 
113,400 
1 13,400 
113,000 
113,400 
113,400 
113.400 
113.000 
113,400 
113,400 
1 13,400 
113,000 
113,400 
113,400 
113,400 
113,000 
113,400 

69,500 
59,100 
700 
34,900 
54,200 
46,300 
58,900 
58,200 
85,600 
51,000 
63,900 
64,500 
49.500 
74,800 
52,300 
51,500 
46,900 
42,100 
68,000 
65,500 
56,300 
32.000 
16.300 
32,400 

9,400 
51,600 
32,300 

4,600 

0 

12,100 

182,500 
172,500 
114.100 
148,300 
167,600 
159,700 
172,300 
171,600 
198,600 
164,400 
177.300 
177.900 
162,500 
188.200 
165,700 
164,900 
159,900 
155,500 
181,400 
178,900 
169,300 
145,400 
129,700 
145,800 
122,400 
165,000 
145,700 
118,000 
113,000 
125.500 

113,000 
113,400 
113.400 
113.400 
113,400 
113.400 
113.400 
113,400 
113,000 
113.400 
113,400 
113,400 
113,000 
113,400 
1 13,400 
113.400 
113.000 
113.400 
113,400 
113,400 
1 13,000 
113,400 
113,400 
113,400 
113.000 
113,400 
113,400 
113,400 
113,000 
113,400 

59.700 
54.300 
700 
35.000 
42.900 
40.400 
55.300 
57.800 
85,100 
53,100 
65,100 
71.400 
40  200 
73,600 
50,800 
50,800 
46,900 
38,500 
67,400 
69.000 
59.500 
27,400 
16,300 
36,000 

9,400 
48.900 
29,400 

4,600 

0 

12,100 

172,700 
167.700 
114,100 
148.400 
156.300 
153,800 
168,700 
171,200 
198.100 
166,500 
178  500 
184,800 
153,200 
187,000 
1M,200 
164,200 
159,900 
151,900 
180,800 
182,400 
172,500 
140,800 
129,700 
149,400 
122,400 
162,300 
142,800 
118,000 
113,000 
125,500 

109,100 
109,400 
109,400 
109,400 
109,400 
109,400 
109,400 
109,400 
109,100 
109,400 
109,400 
109,400 
109.100 
109,400 
109,100 
109,400 
109,100 
109,400 
109,400 
109,400 
109,100 
109,400 
109,400 
109,400 
109,100 
109,'<00 
109,400 
109,400 
109,100 
109,400 

73,000 
67,100 

1,500 
30,400 
47  100 
43,400 
64,500 
54,100 
92,300 
52,800 
74,100 
78.500 
46.200 
76.100 
54.100 
59.300 
54.500 
48,000 
76.500 
72,400 
58,300 
41,700 
14,000 
29,000 

6,500 
45,100 
33,900 

2,500 

0 

20,900 

182,100 
176,500 
110,900 
139,800 
156  500 
152,800 
173,900 
163,500 
201.400 
162,200 
183  500 
187,900 
155,300 
185,500 
163,500 
168.700 
163,600 
157,400 
185,900 
181,800 
167.400 
151.100 
123.400 
138,400 
115.600 
154,500 
143.300 
111.900 
109.100 
130.300 

Average 

113,400 

44,800 

158,200 

113,400 

43,400 

156,800 

109,400 

47,300 

156,700 

•Total  primary  power  production  of  leap  years  taken  the  same  as  in  other  years. 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS. 


117 


VOIR  ON  SACRAMENTO  RIVER. 
YIELD  BY  YEARS 


FLOOD  CONTROL. 

1,  2,  and  4. 

mary,  see  Table  5a,  page  282.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.P.  =  0.80. 


Operating  primarily  for  irrigation 

with  incidental  power  generation 

Seasonal  irrigation  yield  4,276,000  ac.-ft. 

(Deficiency  in  supply  one  year  in  ten.    !> 

0  deduction  for  downstream  prior  rights) 

Average  power  yield  in  kilowatts  (Load  factor=1.00) 

Coordinated  mth  flood  control 

by  reservoir  operating  diagram 

Year 

Without  flood  control 

Maximum  controlled  flow 
at  Red  Bluff  125,000  sec.-ft. 

Maximum  reservoir  space 

required  454,000  acre-feet 

Primary 

Secondary 

Total 

Primary 

Secondary 

Total 

0 

178.400 

178,400 

0 

164,000 

164,000 

1896 

0 

180,800 

180,800 

0 

181,900 

181,900 

1897 

0 

91.200 

91,200 

0 

91,200 

91.200 

1898 

0 

88,700 

88,700 

0 

88,700 

88,700 

1899 

0 

145,500 

145,500 

0 

145,300 

145,300 

1900 

0 

144,900 

144,900 

0 

142.000 

142,000 

1901 

0 

166,300 

166,300 

0 

161,600 

161,600 

1902 

0 

176,700 

176,700 

0 

181.000 

181,000 

1903 

0 

170,200 

170,200 

0 

172,600 

172,600 

1904 

0 

188,300 

188,300 

0 

193.300 

193,300 

1905 

0 

161.500 

161,500 

0 

163,700 

163,700 

1906 

0 

186,200 

186,200 

0 

199,700 

199,700 

1907 

0 

166,000 

166,000 

0 

155,900 

155,900 

1908 

0 

190,400 

190,400 

0 

186,400 

186,400 

1909 

0 

171,100 

171,100 

0 

170,100 

170,100 

1910 

0 

155,500 

155,500 

0 

163,400 

163,400 

1911 

0 

130,200 

130,200 

0 

130,200 

130,200 

1912 

0 

143,800 

143,800 

0 

143,600 

143,600 

1913 

0 

192,800 

192,800 

0 

192,900 

192.900 

1914 

0 

181,100 

181.100 

0 

181,900 

181.900 

1915 

0 

183,300 

183,300 

0 

187,200 

187,200 

1916 

0 

129.700 

129.700 

0 

129,700 

129.700 

1917 

0 

96,400 

96.400 

0 

96,400 

96,400 

1918 

0 

138,500 

138,500 

0 

142,900 

142,900 

1919 

0 

53,400 

53,400 

u 

53,400 

53,400 

1920 

0 

176,800 

176,800 

0 

178,700 

178,700 

1921 

0 

116,700 

116,700 

0 

116,700 

116.700 

1922 

0 

91.100 

91,100 

u 

91,100 

91,100 

1923 

0 

25,600 

25.600 

0 

25,600 

25,600 

1924 

0 

135,500 

135,500 

0 

133.900 

133,900 

1925 

0 

145,300 

145,300 

0 

145,600 

145,600 

Average 

118  WATER   RESOURCES   OF    CALIFORNIA. 

Pardee  Reservoir  on    Mokelumne   River. 

The  East  Bay  Munieii)al  Utility  District  proposes  to  construct  the 
Pardee  reservoir  of  222,000  acre-feet  capacity  at  tiie  site  on  the  Mokel- 
umne River  known  by  many  as  the  Lancha  Plana.  It  is  estimated  that 
this  reservoir  will  yield  200  million  gallons  per  day  equalized  for 
municipal  supply.  The  dam  would  be  345  feet  high.  A  power  plant 
of  15,000  k.w.  capacity  at  its  base  would  generate  electricity  with  the 
water  passing  by  the  dam.  The  effect  of  including  in  the  plans  of  the 
East  Bay  Municipal  Utility  District  a  flood  control  feature  similar  to 
that  devised  for  the  reservoirs  of  the  "Coordinated  Plan"  was  investi- 
gated by  the  Division  of  Engineering  and  Irrigation  under  agreement 
with  the  district  of  date  February  5,  1926. 

The  size  of  floods  to  be  controlled  on  the  Mokelumne  River  is  indi- 
cated by  the  largest  ones  in  the  stream  flow  records.  The  largest  rain- 
water flood  in  the  twenty-one  years  of  measured  flow  occurred  on 
January  30,  1911,  with  a  crest  discharge  of  20,600*  second-feet.  The 
largest  snow-water  flood  occurred  on  June  12,  1906,  with  a  discharge 
of  8740  second-feet.  The  crest  discharge  of  these  floods  could  be  lim- 
ited by  the  Pardee  reservoir  through  the  use  of  a  diagram  like  that 
on  Plate  XIX,  "Reservoir  Operating  Diagram  for  Controlling  Floods 
on  IMokelumne  River"  (p.  80),  to  5300  second-feet  for  rain-water 
floods  and  to  7100  second-feet  for  snow-water  floods.  This  reduction 
in  flood  flows  could  be  obtained  by  the  use  at  times  of  a  maximum 
reserve  for  flood  control  of  92,000  acre-feet,  about  two-fifths  the  total 
capacity  of  the  reservoir. 

The  effect  of  including  this  flood  control  feature  upon  reservoir  stage 
and  the  yield  of  water  and  power  from  the  Pardee  reservoir  is  derived 
from  a  comparison  of  two  sets  of  computations  of  the  yield,  one  with 
and  the  other  without  flood  control.  As  in  studying  the  effect  of  the 
inclusion  of  a  flood  control  feature  upon  the  yield  of  the  Keunett  reser- 
voir, both  sets  of  computations  were  carried  through  the  entire  period  of 
measured  flow^  on  a  daily  basis  instead  of  on  the  usual  monthly  basis  in 
order  to  make  the  set  without  flood  control  exactly  comparable  to  the 
one  with  flood  control  included.  The  latter  had  to  be  carried  through 
on  a  daily  basis  to  accoinniodate  the  requirements  of  the  reservoir 
operating  diagram  which  i-equires  a  daily  atljustment  of  reservoir  level 
during  the  flood  season.  The  stream  flow  data  used  are  those  published 
in  the  Water  Supply  Papers  of  the  United  States  Geological  Survey 
for  the  Clements  gaging  station  together  with  those  in  preparation  for 
publication.  No  deduction  was  made  for  the  59  square  miles  of  drain- 
age area  between  Clements  and  the  dam.  The  assumptions  employed 
in  these  computations  are  listed  on  page  298. 

The  effect  of  including  this  flood  control  feature  upon  the  reservoir 
stage  is  delineated  upon  Plate  XXIV,  "Effect  of  Controlling  Mokel- 

•  Water  Supply  Paper  No.  551  of  the  United  States  Geological  Survey,  recently 
published,  places  the  maximum  discharge  of  the  Mokelumne  River  at  Clements  at 
25,500  second-feet.  This  is  obtained  by  applying  the  rating  curve  of  the  19H  flood 
to  the  gage  heights  of  1907.  The  crest  discharge  of  the  1907  flood  has  been  published 
as  17,000  second-feet  in  former  publications  including  Water  Supply  Paper  No.  299 
in  which  are  printed  the  daily  discharges  of  the  1907  flood.  The  figures  contained  in 
Water  Supply  Paper  No.  299  have  been  used  in  preparing  tiiis  volume.  Should  the 
dally  discharges  of  the  1907  flood  be  revised  by  application  of  the  1907  gage  heights 
to  the  1911  rating  curve,  the  increase  in  their  values  would  be  so  substantial  as  to 
require  a  complete  revision  of  the  analyses  of  floods  on  the  Mokelumne  River  con- 
tained in  this  volume  in  ordor  to  make  the  analyses  harmonize  with  the  increased 
discharge  values. 


PLATE  XXIV. 

r 

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1910 

3RIL                MAY                JUNE 

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rainfall  m  a  normal 

F  Controlling  Mokelumne  River  Flc 

STAGE  OF  PARDEE  RESERVOIR 

IF  OPERATED  PRIMARILY  FOR  MUNICIPAL  SUPPLY 

MAXIMUM  CONTROLLED  FLOW  AT  CLEMENTS 
RAIN  WATER  FLOODS      5,300   SEC   FT. 
SNOW  WATER  FLOODS      7,100   SEC.  FT. 

j            MAXIMUM  FLOOD  OF  RECORD     20,600   SEC   FT. 
1                  RESERVOIR  CAPACITY     222,000    AC  FT. 
MEIGHT   OF  DAM    345  FT. 

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Stsje  of  reservoir  operareO  for  flood  control  alone 

S1»«e  of  rrstrwir  0D«r3Tei)  for  mun-coal  Suppljr  w 
(»»era«e)*nn|tnefsrof  wpacjfjf    of  15,000  K.W.    1  0  B[ 


Dugn  reservoir  for  pnor  ngnrs. 


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X>^-A.-^      Mtan  dailj  flow([Onlnjlltd)  of  H 


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from  records  of  United  States  Oeclogital  Sui 
r  operated  for  municipal supplj  with  incjdeniai  pon 


Effect  of  Controlling  Mokelumne  River  Floods 

STAGE  OF  PARDEE  RESERVOIR 

IF  OPERATED  PRIMARILY  FOR  MUNICIPAL  SUPPLY 

MAXIMUM  CONTROLLED  FLOW  AT  CLEMENTS 
BAIN  WATER  FLOOOS      5.300  SEC   FT 
SNOW  WATER  FLOODS      7, 1 00  SEC   FT. 

MAXIMUM  FLOOD  OF  RECORD     20.600   SEC   FT. 

RESERVOIR  CAPACITY    222.000    AC  FT, 

HEIGHT   OF  0AM    345  FT. 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  121 

umiie  River  Floods  lipori  Staoo  of  Pardee  Reservoir."  It  is  assumed 
in  preparing  this  plate  that  the  Pardee  reservoir  was  constructed  some 
time  prior  to  1904,  the  opening  year  of  continuous  stream  flow  measure- 
ments on  the  Mokelumne  River,  and  operated  both  with  and  without 
flood  control  through  the  succeeding  years  for  a  municipal  supply  of 
200  million  gallons  per  day  together  with  incidental  power  development 
as  proposed  by  the  East  Bay  Municipal  Utility  District.  The  reservoir 
stage  for  every  day  of  the  21  years  from  1905  to  1926  is  indicated  by 
lines  extending  across  the  plate  in  several  rows.  Their  vertical  posi- 
tion, read  on  the  reservoir  stage  scale,  shows  the  number  of  acre-feet 
of  water  in  storage  at  all  times.  On  this  scale,  the  space  between 
parallel  guide  lines  represents  20,000  acre-feet  of  reservoir  capacity. 
The  top  guide  line  of  each  row  represents  a  full  reservoir  and  the 
bottom  one  an  empty  reservoir. 

The  heavy  black  line  extending  across  each  row  indicates  the  stagd 
were  200  million  gallons  per  day  drawn  from  the  reservoir  and  140,000 
acre-feet  per  year  passed  by  the  dam  for  prior  rights.  The  heavy  red 
line  indicates  the  departures  from  this  stage  by  reason  of  the  introduc- 
tion of  the  flood  control  feature.  The  light  red  line  indicates  the 
stage  w^ere  the  reservoir  operated  for  flood  control  alone  in  accordance 
with  the  diagram.  Red  figures  translate  into  feet  of  depth  the  greatest 
draw  down  from  a  full  reservoir  required  by  flood  control  during  each 
season.  A  light  black  line  in  each  row  below  the  reservoir  stage  lines 
indicates  on  a  special  scale  superimposed  on  the  reservoir  stage  scale, 
the  undisturbed  daily  flow  in  the  IMokelumne  River  at  Clements,  The 
light  red  line  close  at  hand  shows  the  flow  below  the  dam  as  controlled 
by  the  coordinate  operation  of  the  reservoir  for  flood  control  and  con- 
servation. A  black  dotted  line  shows  throughout  the  flood  season  the 
daily  value  of  the  progressive  rainfall  index  used  in  entering  the 
reservoir  operating  diagram  to  obtain  the  flood  control  reserve  on  each 
day. 

In  8  out  of  the  21  seasons  displayed  on  the  plate,  flood  control 
requires  a  maximum  dei>th  of  empty  space  from  50  to  52.5  feet  below 
the  full  reservoir  level.  In  the  other  13  seasons,  the  maximum  depths 
required  range  from  0  to  50  feet.  In  one-third  of  the  seasons,  the  water 
level  due  to  conservation  operations  is  lower  than  required  for  flood 
control.  The  average  actual  depression  of  water  level  due  to  flood 
control  is  10  feet,  3.4  per  cent  of  the  average  depth  of  water  in  the 
reservoir  at  the  dam.  The  reservoir  level  is  depressed  for  flood  control 
more  than  one  foot,  about  one-quarter  of  the  entire  elapsed  time  of  the 
analysis. 

The  water  yield  of  the  reservoir  is  practically*  the  same  both  with 
and  without  the  inclusion  of  the  flood  control  feature.  A  continuous 
draft  of  200  million  gallons  per  day  can  be  sustained  through  the  entire 
21  years  either  with  or  without  flood  control  except  in  the  fall  of  1924 
when  there  is  a  .shortage  of  19.9  billion  gallons  with  and  19.1  billion 
gallons  without  flf)0(l  couti-ol,  a  diffci-once*  of  1.1  per  cent  of  the  annual 
supply. 


•  It  appears  probable  that  the  yield  of  water  and  power  both  with  and  without 
flood  control  would  be  the  same  were  indices  of  snow-on-the-^ound  used  instead  of 
rainfall  indices  in  constructing  and  applying  that  part  of  the  reservoir  operating 
diagram  pertaining  to  snow-water  floods   (sec  page  213). 


122  WATER   RESOURCES   OP    CALIFORNIA. 

The  average  incidental  power  generated  is  6640  kilowatts  without 
flood  control  and  6510  kilowatts  with  flood  control,  a  difference  of  2 
per  cent.    In  both  instances  the  entire  amount  is  secondary  power. 

If  flood  control  were  attained  by  holding  the  maximum  reserve  empty 
throughout  the  flood  season  the  inclusion  of  flood  control  would  affect 
the  yield  of  water  and  poAver  a  little  more  than  if  attained  by  use  of 
the  reservoir  operating  diagram.  In  the  computations  for  this  com- 
parison, 92,000  acre-feet  of  capacity  are  held  empty  each  year  until 
April  21st,  the  close  of  the  rain-water  flood  season.  The  reserve  is  then 
reduced  to  13,000  acre-feet.  This  is  held  empty  from  May  11th  to 
July  5th,  the  season  of  snow-water  floods.  Under  this  plan  of  opera- 
tion, flood  control  increases  the  shortage  in  water  yield  in  1924,  the 
only  year  of  deficient  supply,  from  19.1  to  24.6  billion  gallons,  an 
increase  of  2.8  per  cent  of  the  annual  supply.  A  full  supply  is  obtained 
in  all  of  the  other  20  years  analyzed.  The  average  power  output  is 
reduced  2.9  per  cent. 

The  following  tables  present  yearly  summaries  of  all  the  computa- 
tions of  yield  of  the  reservoir.  Tables  of  monthly  summaries,  because 
of  their  volume,  are  placed  in  a  separate  chapter. 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  123 


PARDEE  RESERVOIR  ON   MOKELUMNE  RIVER 

Table  of  Yearly  Summaries  of  Water  and   Power  Yield  Computed  on  a 

Daily   Basis 

Showing  the  effect  of  inclusion  of  the  flood  control  feature. 

(See  Chapter  VIII  for  corresponding 
monthly  summaries.) 

Table  6 — With  and  without  flood  control  by  reservoir  operating  diagram. 

Table  7 — Yield  compared  for  two  methods  of  flood  control. 

Table  8 — Summary  of  Tables  6  and  7. 


124 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  6.     PARDEE  RESERVOIR 

WATER  AND 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 


Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


Yearly  Summary  of  Computations 

For  corresponding  monthly  sum 


Run-off 

Without  flood  control 

Power 

Year 

at 
Gements 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
year  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

draft 
through 
turbines 
including 
water 
passed 
for  prior 
rights  in 
acre-feet 

Evapora- 
tion in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

lalowatts 
(Load 

factor= 
1.00) 

1905 

578,060 

145,860 

224.040 

241,480 

5,860 

135,880 

0 

303 

6.320 

1906 

1,415,400 

116,660 

224,040 

325,760 

6,400 

794,280 

0 

307 

8.650 

1907 

1.642,700 

181,580 

224,040 

398,680 

6,150 

1.046,510 

0 

313 

10.820 

1908 

455.340 

148,900 

224,650 

236.970 

5,820 

10,770 

0 

299 

6.020 

1909 

1.278,230 

126,030 

224,040 

346,350 

6,160 

618,790 

0 

315 

9,480 

1910 

788,060 

208,920 

224,040 

279,830 

5,740 

355.440 

0 

314 

7.670 

1911 

1,51.5.830 

131,9.30 

224,040 

315.670 

6,210 

970,250 

0 

311 

8,630 

1912 

410,540 

131,590 

224,650 

169,020 

.5,340 

10,360 

0 

279 

3,870 

1913 

405,950 

132,760 

224.040 

183,270 

5,820 

3,280 

0 

286 

4,370 

1914 

1,075.890 

122,300 

224,040 

302.610 

6,240 

541,320 

0 

314 

8,280 

1915 

829  400 

123,980 

224,040 

248,280 

6,210 

336,460 

0 

303 

6.580 

1916 

1,049,320 

138,390 

224,650 

303,750 

6,210 

508,860 

0 

308 

8,240 

1917 

828,860 

144,240 

224,040 

275,060 

6,260 

352,930 

0 

302 

7.190 

1918 

546,170 

114,810 

224,040 

179,270 

6,220 

116,680 

0 

293 

4.680 

1919 

573,130 

134,770 

224,040 

196,310 

5,720 

171,570 

0 

294 

4,970 

1920 

506,310 

110,260 

224,650 

159,980 

5.870 

64,340 

0 

283 

3,930 

1921 

823,280 

161.730 

224,040 

282,720 

5,890 

345,540 

0 

313 

7,660 

1922 

974,010 

126,820 

224,040 

243,190 

6,300 

450,540 

0 

301 

6,390 

1923 

648,880 

176,760 

224,040 

313,070 

5,860 

152,490 

0 

300 

7.930 

1924 

206,650 

130,180 

166,010 

140,000 

1,760 

0 

58,W0 

208 

2,590 

1925 

802,990 

29,060 

224,040 

190,680 

6.610 

277,080 

0 

288 

5,100 

Total 

17,355,000 

4,649,250 

5,331,950 

122.650 

7,263.370 

58,640 

Average 

826,430 

221,390 

253,900 

5,840 

345,870 

2,790 

296 

6,640 

THE    CONTROL   OF    FLOODS   BY   RESERVOIR.S. 


125 


ON  MOKELUMNE  RIVER. 
POWER  YIELD 


BY  RESERVOIR  OPERATING  DIAGRAM. 

Carried  out  on  a  Daily  Basis. 

mary  see  Table  6a,  page  300.) 

Yield  in  municipal  supply  200  million  gallons  daily. 

Installed  capacity  of  power  plant  15,000  k.w. 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Clements— rain-water  floods,  5,300  sec.-f  t;  snow-water  floods,  7,100  sec.-f  t. 
Maximum  reservoir  space  required — rain-water  floods,  92,000  ac.-ft.;  snow-water  floods,  13,000  ac.-ft. 

Stage  of 
reservoir 

at 
beginning 

of 
year  in 
acre-feet 

Municioal 

draft 

in 

acre-feet 

Power 

draft 

through 

turbines 

including 

water 

passed 

for  prior 

rights  in 

acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 

over 
spillway 

in 
acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor^ 
1.00) 

Year 

145,860 
114,640 
165,670 
148,900 
126,030 
160,810 
121,390 
131,590 
132,760 
122,300 
123,980 
138,390 
144,240 
114,810 
134,770 
110,260 
161,730 
124,600 
176,760 
127,850 
29,060 

224,040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
163,680 
224,040 

241,160 
330,460 
415,450 
236,970 
345,820 
269,630 
339,400 
169,020 
183,270 
328,090 
230,140 
339,580 
259,550 
179,270 
196,310 
159,980 
280,900 
235,780 
288,000 
140,000 
189,850 

5,860 
6,400 
6,150 
5,820 
6,160 
5,740 
6,210 
5,340 
5,820 
6,240 
6,210 
6,210 
6,260 
6,220 
5,720 
5,870 
5,890 
6,300 
5,860 
1.760 
6,610 

111,840 

571,150 

521,260 

0 

552,980 

224,410 

730,430 

0 

0 

449,110 

333,570 

346,920 

263,350 

0 

0 

0 

293,730 

394,730 

169,370 

0 

182,850 

26,380 

232,320 

492,570 

10,770 

114,450 

103,660 

205,550 

10,360 

3,280 

66,730 

21,030 

126,110 

105,090 

116,680 

171,570 

64,340 

55,850 

61,000 

10,520 

0 

99,770 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
60,970 
0 

302 
305 
305 
299 
304 
298 
302 
279 
286 
302 
302 
298 
302 
293 
294 
283 
302 
300 
297 
206 
286 

6,300 
8,680 
10,820 
6,020 
9,010 
6,900 
8,850 
3,870 
4,370 
8,450 
6,080 
8,690 
6,790 
4,680 
4,970 
3,930 
7,170 
6,220 
7,250 
2,570 
5,040 

1905 
1906 
1907 
1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 

4,646,920 
221,280 

5,358,630 
255,170 

122,650 
5,840 

5,145,700 
245,030 

2,098,030 
99,910 

60,970 
2,900 

292 

6.510 

Total 
Average 

126 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  7.     PARDEE  RESER 

CX>MPARISON  OF  WATER 

FOR 

TWO  METHODS  OF 

Yearly  Summary  of  Computations 

(For  corresponding  monthly  sum 


Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


Run-off 

at 
Clements 

in 
acre-feet 

Fleod  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Clements— rain-water  floods,  5,300  sec.-ft.; 

snow-water  floods,  7,100  sec.-ft. 

Maximum  reservoir  space  required — rain-water  floods,  92,000  ac.-ft.; 

snow-water  floods,  13,000  ac.-ft. 

Year 

Stage  of 
reservoir 

at 
beginning 

of 
year  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

Power 

draft 

through 

turbines 

including 

water 

passed 

for  prior 

rights  in 

acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

1905 
1906 
1907 
1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 

578,060 

1,415,400 

1,642,700 

455,340 

1,278,230 

788.060 

1.515,830 

410,540 

405,950 

1,075,890 

829,400 

1,049,320 

828.860 

546,170 

573,130 

506,310 

823,280 

974,010 

648,880 

206.650 

802,990 

145,860 
114,640 
165,670 
148,900 
126,030 
160,810 
121,390 
131.590 
132.760 
122.300 
123.980 
138.390 
144.240 
114.810 
134.770 
110,260 
161,730 
124,600 
176,760 
127.850 
29,060 

224,040 
224,040 
224,040 
224,650 
224,040 
224.040 
224.040 
224,650 
224,040 
224,040 
224,040 
224,650 
224  040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
163,680 
224,040 

241.160 
330.460 
415.450 
236,970 
345,820 
269,630 
339,400 
169,020 
183,270 
328,090 
230,140 
339,580 
259,550 
179,270 
196,310 
159,980 
280,900 
235,780 
288.000 
140.000 
189.850 

5,860 
6,400 
6,150 
5,820 
6.160 
5.740 
6.210 
5.340 
5.820 
6.240 
6.210 
6.210 
6,260 
6.220 
5.720 
5,870 
5.890 
6.300 
5.860 
1,760 
6,610 

111.840 

571,150 

521,260 

0 

552,980 

224,410 

730,430 

0 

0 

449.110 

333.570 

346.920 

263,350 

0 

0 

0 

293,730 

394,730 

169,370 

0 

182,850 

26,380 

232,320 

492,570 

10,770 

114,450 

103,660 

205.550 

10,360 

3,280 

66,730 

21,030 

126,110 

105,090 

116.680 

171.570 

64.340 

55.850 

61.000 

10,520 

0 

99,770 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
60,970 
0 

302 
305 
305 
299 
304 
298 
302 
279 
286 
302 
302 
298 
302 
293 
294 
283 
302 
300 
297 
208 
286 

6,300 
8,680 
10,820 
6.020 
9.010 
6,900 
8,850 
3,870 
4,370 
8.450 
6,080 
8,690 
6,790 
4,680 
4.970 
3,930 
7,170 
6.220 
7,250 
2.570 
5.040 

Total 
Average 

17.355.000 
826.430 

4,646,920 
221,280 

5,358.630 
255,170 

122.650 
5,840 

5,145,700 
245,030 

2,098,030 
90  910 

60,970 
2,900 

292 

6.510 

THE  CONTROL  OF  FLOODS  BY  RESERVOIRS. 


127 


VOIR  ON  MOKELUMNE  RIVER. 
AND  POWER  YIELD 


FLOOD  CONTROL. 

Carried  out  on  a  Daily  Basis. 

mary,  see  Table  7a,  page  312.) 


Yield  in  municipal  supply  200  million  gallons  daily. 
Installed  capacity  of  power  plant  15,000  k.w. 


Flood  control,  holding  maximum  reservoir  space  required  (rain-water  floods,  92,000  ac.-ft. 

snow-water  floods,  13,000  ac.-ft.)  in  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Clements— rain-water  floods,  5,300  sec.-f  t. ;  snow-water  floods,  7,100  sec.-f  t. 

Stage  of 
reservoir 

at 
beginning 

of 
year  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

Power 

draft 

through 

turbines 

including 

water 

passed 

for  prior 

rights  in 

acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in_ 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

Year 

101,560 
103,660 
130,000 
123,510 
113,040 
124,900 
118,910 
115,200 
109.050 
109,280 
118,860 
127,440 
129,190 
108,520 
121,490 

97,250 
130,000 
113,830 
130,000 
113,190 

29,060 

224,040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
149,020 
224,040 

234,520 
352,970 
412,760 
217,880 
386,170 
290,070 
347,480 
169,220 
175,860 
331,090 
253,800 
340,750 
262,890 
189,640 
193,870 
177,420 
301,710 
256,700 
299,750 
140,000 
214,330 

5,860 
6,400 
6,150 
5,820 
6,160 
5,740 
6,210 
5,340 
5,820 
6,240 
6,210 
6,210 
6,260 
6,220 
5,720 
5,870 
5,890 
6,300 
5,860 
1,760 
6,610 

111,540 
657,380 
864,760 

17,460 
617,970 
255,830 
877,030 

17,480 
0 
504,940 
336,770 
434,230 
350,310 
113,300 
134,780 

65,620 
307,810 
444,980 
136,040 
0 
248,080 

0 

148,270 

141,480 

0 

32.030 

18,370 

64,780 
0 
0 
0 
0 

41,730 

6,030 

0 

38,960 
0 
0 

25,820 
0 
0 

18.280 

0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
75,630 
0 

285 
295 

298 
285 
292 
290 
295 
267 
273 
294 
293 
292 
293 
284 
286 
274 
292 
291 
282 
198 
279 

5,700 
8,850 
10,560 
5,220 
9,490 
7,090 
8,750 
3,700 
3,950 
8,200 
6,340 
8,450 
6,580 
4,730 
4,760 
4,230 
7,440 
6,420 
7,010 
2,450 
5,420 

1905 
1906 
1907 
1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 

4,632,260 
220,580 

5,548,880 
264,230 

122,650 
5,840 

6,496,310 
309.350 

535,750 
25,510 

75,630 
3  600 

283 

6,450 

Total 

Average 

128 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  8.     PARDEE  RESERVOIR  ON  MOKELUMNE  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  YEARS 

BOTH 
WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  6  and  7. 

(For  corresponding  monthly  summary,  see  Table  8a,  page  324.) 

Height  of  dam  345  feet.        Yield  in  municipal  supply  200  million  gallons  daily. 
Capacity  of  reservoir  222,000  ac.-ft.    Installed  capacity  of  power  plant  15,000  k.w. 


Year 

Without  flood  contro 

Coordinated  with  flood  control  by 
reservoir  operating  diagram 

Maximum  controlled  flow  at 

Clements — rain-water  floods. 

5,300  sec.-ft.;  snow-water 

floods,  7,100  sec.-ft. 

Maximum  reservoir  space 

required — rain-water  floods 

92,000  ac.-ft.;  snow-water 

floods.  13,000  ac.-ft. 

Flood  control,  holding  maximum 

reservoir  space  required  (rain-water 

floods.  92,000  ac.-ft.;  snow-water 

floods,  13,000  ac.-ft.)  In  reserve 

throughout  flood  season 

Maximum  controlled  flow  at 

Clements — rain-water  floods, 

5,300  sec.-ft.;  snow-water 

floods,  7,100  sec.-ft. 

Municipal 
draft  in 
acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 
power 

jield  in 

lalowatts 
(Load 

factor= 
].00) 

Municipal 
draft  in 
acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 
power 

yield  in 

Icilowatts 
(Load 

factor= 
1.00) 

Municipal 
draft  in 
acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

1905 
1906 
1907 
1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 

224,040 
224,040 
224,040 
224,650 
22-1,040 
224,040 
224,040 
224.650 
224,040 
224,040 
224,040 
224.650 
224,040 
224,040 
224.040 
224,650 
224,040 
224,040 
224,040 
166,010 
224,040 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
58,640 
0 

6,320 
8,650 
10,820 
6,020 
9,480 
7,670 
8,630 
3,870 
4,370 
8,280 
6.580 
8,240 
7,190 
4,680 
4,970 
3,930 
7,660 
6,390 
7,930 
2.590 
5,100 

224,040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
163,680 
224,040 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
60,970 
0 

6,300 
8,680 
10,820 
6,020 
9,010 
6,900 
8,850 
3.870 
4,370 
8,450 
6,080 
8,690 
6,790  • 
4.680 
4,970 
3,930 
7,170 
6,220 
7,250 
2,570 
5,040 

224,040 
224,040 
224,040 
224,650 
224,040 
224,040 
224,040 
224,650 
224,040 
224,010 
224,040 
224,650 
224,040 
224,040 
224,040 
224,650 
224.040 
244,040 
224,040 
149.020 
224,040 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
75,630 
0 

6.700 
8.850 
10,660 
6,220 
9,490 
7,090 
8,760 
3.700 
3,950 
8,200 
6,340 
8,450 
6,580 
4,730 
4.760 
4,230 
7,440 
6.420 
7.010 
2,450 
5.420 

Total 
Average 

4,649,250 
221.390 

58,640 
2,790 

6,640 

4,646,920 
221,280 

60,970 
2,900 

6.510 

4.632,260 
220,580 

75,630 
3,600 

6.450 

Temperance   Flat   Reservoir  on   San  Joaquin   River. 

Among  the  reservoirs  of  the  "Coordinated  Plan,"*  for  developing 
the  State's  waters  is  one  on  the  San  Joaquin  River,  six  miles  upstream 
from  Friant.  It  is  proposed  that  a  dam  595  feet  high  be  constructed  at 
this  point.  This  would  create  a  reservoir  of  1,071, OOO  acre-feet  capac- 
ity, sufficiently  large  lo  ('(ju.ilize  seven-eighths  of  the  mean  annual 
run-off  of  the  San  Joa(|uin  Kivei*  for  irrigation  use  and  generate  on  an 
average  62,000  kilowall.s  of  incidental  power  at  a  plant  erected  near 
the  base  of  the  dam.  The  installed  capacity  of  the  plant  would  be 
220,000  k.v.a.     Also,  large  floods  would  be  controlled  to  about  one- 

•  See  Bui.  No.  12,  "Summary  Report  on  the  Water  Resources  of  California  and  a 
Coordinated  Plan  for  their  Development,"  Division  of  Engineering  and  Irrigation, 
State  Department  of  Public  Works. 


THE    CONTROL    OF    FLOODS    BY    RESERVOIRS.  129 

quarter  of  their  natural  size.  A  full  description  of  this  unit  of  the 
"Coordinated  Plan,"  together  with  estimate.s  of  the  water  and  power 
yield  without  flood  control  is  contained  in  Bulletin  No.  16,  ' '  The  Coor- 
dinated Plan  of  Water  Development  in  the  San  Joaquin  Valley."  The 
effect  of  including  the  flood  control  feature  of  the  plan  is  described  in 
the  following  pages. 

The  rule  for  operating  the  Temperance  Flat  Keservoir  for  flood  con- 
trol has  been  developed  in  the  previous  chapters  of  this  volume.  It  is 
expressed  on  Plate  XX,  ' '  Reservoir  Operating  Diagram  for  Controlling 
Floods  on  the  San  Joaquin  River"  (p.  84).  It  would  limit  rain-water 
floods,  including  the  maximum  of  record,  to  10,700  second-feet  and 
snow-water  floods  to  14,200  second-feet.  The  maximum  rain-water 
flood  of  record  had  a  mean  daily  flow  of  38,800  second-feet.  It  occurred 
on  Jan.  31,  1911.  The  maximum  snow-water  flood  discharged  23,100 
second-feet  and  occurred  on  June  13,  1911.  The  reduction  in  flood 
flows  obtained  through  the  use  of  this  reservoir  operating  diagram 
requires  a  reservation  at  times  of  a  maximum  space  of  177,000  acre- 
feet,  one-sixth  of  the  total  capacity  of  the  reservoir. 

The  effect  of  including  this  flood  control  feature  upon  the  reservoir 
stage  and  upon  the  yield  of  water  and  power  is  derived  from  a  com- 
parison of  the  yield  computed  both  with  and  without  flood  control.  In 
order  that  this  might  be  an  exact  comparison,  both  sets  of  computations 
are  carried  out  on  a  daily  basis  to  conform  to  the  requirements  of  the 
reservoir  operating  diagram  which  calls  for  daily  adjustment  of  reser- 
voir level  during  the  flood  seaso2i.  The  parallel  sets  of  computations 
are  made  in  exactly  the  same  way  except  for  the  exclusion  of  the  flood 
control  feature  in  one  set.  They  are  carried  out  similarly  to  the  com- 
putations of  yield  described  in  Bulletin  No.  16,  except  that  they  are 
made  on  a  daily  instead  of  the  u.sual  monthly  basis,  include  only  the  18 
years  of  continuous  stream  flow  record  and  make  no  deduction  for  the 
108  square  miles  of  drainage  area  between  the  Friant  gaging  station  and 
the  dam  site.*  The  stream  flow  data  used  are  those  published  in  the 
Water  Supply  Papers  of  the  United  States  Geological  Survej"  for  the 
Friant  gaging  station  together  with  those  in  preparation  for  publi- 
cation.   The  assumptions  of  the  computations  are  listed  on  page  331. 

The  effect  of  inclusion  of  the  flood  control  feature  upon  reservoir 
stage  is  delineated  on  Plate  XXV,  "Effect  of -Controlling  San  Joaquin 
River  Floods  upon  Stage  of  Temperance  Flat  Reservoir."  Here  the 
reservoir  stage  is  shov/n  day  b}'  day  from  1908  to  1926,  the  period  of 
continuous  measurement  of  flow  in  the  San  Joaquin  River.  It  is 
assumed  for  constructing  this  plate  that  the  reservoir  was  in  existence 
in  1907  and  operated  through  the  succeeding  years  as  proposed  in  the 
"Coordinated  Plan,"  flr.st  excluding  and  then  including  the  flood  con- 
trol feature.  The  volume  of  water  in  storage  throughout  the  18-year 
period  is  shown  on  each  day  by  the  vertical  position  on  the  reservoir 
stage  scale  of  lines  extending  across  the  plate  in  several  rows.  To  the 
scale  of  the  plate,  each  space  between  horizontal  guide  lines  e(iuals 
100,000  acre-feet.  The  top  guide  line  of  each  row  represents  a  full 
re.servoir  and  the  bottom  line  an  empty  reservoir. 


*  The  water  and  power  yield  published  in  Bui.  No.  IG  is  an  estimate  made  on  a 
monthly  basis  covering  the  54-year  period  1871-1925.  It  makes  a  deduction  of  1.5 
per  cent  from  the  measured  flow  at  Friant  for  the  area  between  the  gaging  station 
and  the  dam  site.  For  this  reason  the  estimates  in  Bui.  No.  16  are  not  exactly 
comparable  with  the  ones  contained  in  this  volume. 


130  WATER   RESOURCES   OF    CALIFORNIA. 

The  reservoir  stage  operating  with  the  flood  control  feature  excluded 
is  indicated  by  the  heavy  black  line  extending  across  each  row.  The 
departure  from  this  stage  caused  by  the  inclusion  of  the  flood  control 
feature  is  shown  by  a  heavy  red  line.  A  light  red  line  indicates  the 
reservoir  stage  were  it  operated  for  flood  control  alone  in  accord  with 
the  diagram.  Red  figures  translate  into  feet  depth  from  full  reservoir 
level,  the  greatest  draw  down  required  by  flood  control  in  each  season. 
Below  the  reservoir  stage  lines  in  each  row  is  shown  in  a  light  black 
line  to  a  special  scale  superimposed  on  the  reservoir  stage  scale,  the 
uncontrolled  flow  of  the  river  at  Friant  and  in  a  light  red  line  the  con- 
trolled flow  downstream  from  the  dam  when  the  "Coordinated  Plan" 
with  its  flood  control  feature  is  in  operation.  A  line  of  black  dots 
shows  the  daily  values  of  the  progressive  rainfall  index  used  in  entering 
the  reservoir  operating  diagram  to  obtain  the  necessary  flood  control 
reserve. 

It  is  observed  in  reviewing  Plate  XXV  that  in  12  of  the  18  seasons 
analyzed,  the  reservoir  stage  resulting  from  operation  for  conservation 
is  less  than  that  required  for  flood  control.  In  these  seasons  the 
inclusion  of  the  flood  control  feature  does  not  affect  the  reservoir  stage 
at  all.  In  the  other  six  seasons  at  times,  the  drawdown  from  a  full 
reservoir  level  reaches  a  maximum  of  35  feet,  6  per  cent  of  the  depth 
of  a  full  reservoir  at  the  dam.  The  average  actual  depression  of  the 
water  level  due  to  flood  control  is  17  feet,  3.5  per  cent  of  the  average 
depth  of  water  in  the  reservoir  at  the  dam.  The  reservoir  level  is 
depressed  by  reason  of  the  inclusion  of  the  flood  control  feature,  one- 
quarter  of  the  entire  elapsed  time  of  the  analyses. 

The  effect  of  the  inclusion  of  the  flood  control  feature  in  the  ' '  Coor- 
dinated Plan"  upon  the  water  and  power  yield  of  the  Temperance 
Plat  reservoir  is  shown  by  the  accompanying  summary  tabulations  of 
the  computations  of  yield  with  and  without  flood  control  carried  out  on 
a  dail.y  basis  in  order  to  accommodate  the  requirements  of  the  reservoir 
operating  diagram.  Monthly  and  yearly  summaries  are  prepared  of 
these  computations.  The  yearly  summaries  follow  herewith  but  the 
monthly  summaries,  because  of  their  volume,  are  placed  in  a  separate 
chapter. 

These  data  show  that  the  inclusion  of  tlie  flood  control  feature  has 
no  effect  at  all  upon  the  water  yield  of  the  reservoir  and  very  little 
effect*  upon  the  power  generated.  With  flood  control  the  average 
power  output  is  61,400  kilowatts  and  without  flood  control  62,000 
kilowatts,  a  difference  of  1.0  per  cent.  All  is  secondary  power  in  both 
instances. 

If  flood  control  were  attained  by  holding  the  maximum  reserve 
empty  throughout  the  flood  season  instead  of  by  use  of  the  reservoir 
operating  diagram,  the  inclusion  of  flood  control  would  have  a  small 
effect  on  the  water  as  well  as  on  the  power  yield.  In  the  computations 
for  this  comparison,  133,000  acre-feet  of  capacity  are  held  empty  each 
year  until  April  7th,  the  close  of  the  rain-water  flood  season.  The 
reserve  is  then  increased  to  177,000  acre-feet  which  is  held  empty  from 
April  27th  to  July  16th,  the  season  of  snow-water  floods.  For  these 
condilions,  the  average  yield  of  irrigation  water  is  reduced  1.0  per 
cent,  the  reductions  occurring  in  the  seasons  of  short  supply,  and  the 
average  power  output  is  reduced  6.0  per  cent. 

•  It  appears  probable  that  the  power  yield  would  be  almost  identical  .both  with 
and  without  flood  control  were  indices  of  snow-on-the-ground  used  instead  of  rainfall 
indices  in  constructing  and  applying  that  part  of  the  reservoir  operating  diagram 

nertainincr    tn    onritir-H'O  f  c    fl^rxlo     C  ooo    r^      01•}^  — -      —      — - 


PLATE   XXV. 


-25 


Effect  of  Controlling  San  Joaquin  River  Floods 


UPON 

STAGE  OF  TEMPERANCE  FLAT  RESERVOIR 

IF  OPERATED  PRIMARILY  FOR  IRRIGATION 

MAXIMUM  CONTROLLED  FLOW  AT  FRIANT 
RAIN  WATER  FLOODS    10.700  SEC.  FT 
SNOW  WATER  FLOODS    14,200  SEC.  FT. 

MAXIMUM  FLOOD  OF  RECORD     38,800  SEC.  FT. 

RESERVOIR  CAPACITY    1,071,000   AC.  FT. 

HEIGHT  OF  DAM   595  FT. 


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J 

THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  133 


TEMPERANCE  FLAT  RESERVOIR  ON  SAN  JOAQUIN  RIVER. 

Table  of  Yearly  Summaries  of  Water  and  Power  Yield  Computed  on  a 

Daily  Basis. 

Showing  the  effect  of  inclusion  of  the  flood  control  feature  of  the 

"Coordinated   Plan."      (See    Chapter    VIII    for 

corresponding  monthly  summaries.) 

Table     9 — With  and  without  flood  control  by  reservoir  operating  diagram. 

Table  10 — Yield  compared  for  two  methods  of  flood  control. 

Table  11 — Summary  of  Tables  9  and  10. 


^..t»t  iiiu  power  yield  would   be  almost  identical  .both  with 

ana  without  flood  control  were  indices  of  snow-on-the-ground  used  instead  of  rainfall 
indices  In  constructing  and  applying  that  part  of  the  reservoir  operating  diagram 


1 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  133 


TEMPERANCE  FLAT  RESERVOIR  ON  SAN  JOAQUIN  RIVER. 

Table  of  Yearly  Summaries  of  Water  and  Power  Yield  Computed  on  a 

Daily  Basis. 

Showing  the  effect  of  inclusion  of  the  flood  control  feature  of  the 

"Coordinated    Plan."      (See    Chapter    VIII    for 

corresponding  monthly  summaries.) 

Table     9 — With  and  without  flood  control  by  reservoir  operating  diagram. 

Table  10 — Yield  compared  for  two  methods  of  flood  control. 

Table  11 — Summary  of  Tables  9  and  10. 


134 


WATER   RESOURCES    OF    CALIFORNIA. 


TABLE  9.     TEMPERANCE  FLAT  RESER 

WATER  AND 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Yearly  Summary  of  Computations 

(For  corresponding  monthly  sum 


Height  of  dam  595  feet. 

Capacity  of  reservoir  1,071,000  acre-feet. 


Run-o£f 

Without  flood  control 

at 

Irrigation 

Average 

Year 

Friant 

Stage  of 

draft  in 

Deficiency 

power 

Average 

in 

reservoir 

acre-feet 

Power 

Waste 

head 

power 

acre-feet 

at 

(no 

Evapora- 

draft 

over 

in 

irrigation 

supply 

through 

yield  in 

beginning 

deduction 

tion  in 

through 

spillway 

period 

kilowatts 

of 

for  down- 

acre-feet 

turbines 

in 

of 

(Load 

year  in 

stream 

in  acre-feet 

acre-feet 

in 
acre-feet 

operation 

factor= 

acre-feet 

prior 

in 

1.00) 

rights) 

feet 

1908 

1,115,000 

797.100 

1,800,000 

13,700 

1,699,100 

0 

0 

488 

73,800 

1909 

3,136,700 

98,400 

1,800,000 

18,400 

1,811,400 

568,600 

0 

510 

85,800 

1910 

.1,825,500 

836.700 

1,800,000 

18,500 

1,876,600 

347,300 

0 

538 

91.100 

1911 

3,562,200 

419,800 

1,800,000 

20,100 

1,831,700 

1,416,500 

0 

556 

91,900 

1912 

1,023,700 

713,700 

1,686,900 

10,200 

1,510,300 

0 

113,100 

454 

60,900 

1913 

874,100 

40,300 

863,300 

100 

0 

0 

936,700 

0 

0 

1914 

2,905,300 

51,000 

1,800,000 

18,900 

1,811,600 

361,100 

0 

514 

86,600 

1915 

1.954,600 

764,700 

1,800,000 

19.200 

1,808,300 

250,400 

0 

540 

88,700 

1916 

2,827,000 

641,400 

1,800,000 

20,200 

1,868,800 

849,600 

0 

557 

93,500 

1917 

1,860,100 

729,800 

1,800,000 

18,900 

1,804,700 

176,900 

0 

537 

88,100 

1918 

1,596,500 

589,400 

1,800,000 

14,600 

1,800,000 

0 

0 

466 

77,700 

1919 

1,191,400 

371.300 

1,505,700 

8,300 

1,302,600 

0 

294,300 

416 

49.200 

1920 

1,362,000 

48.700 

1,320.700 

2,400 

420,900 

0 

479,300 

329 

12.300 

1921 

1,580,300 

87.600 

1,576,000 

5,600 

1,361,500 

0 

224,000 

344 

42.700 

1922 

2,376,800 

86,300 

1,800,000 

15,000 

1,652,700 

0 

0 

443 

69.300 

1923 

1,604.900 

648,100 

1,800,000 

16,400 

1,800,000 

0 

0 

500 

82,900 

1924 

466,100 

436,000 

844,300 

1,900 

536,400 

0 

955,700 

394 

17,800 

1925 

1.413.400 

56,500 

1,387,600 

2,600 

111,400 

0 

412,400 

298 

2,900 

T.tal 

32.675.600 

28,984,500 

225,000 

25,008,000 

3,970,400 

3,415,500 

Average 

1,815,300 

1,610,300 

12,500 

1,389,300 

220,600 

189,700 

490 

62,000 

THE   CONTROL    OF   FLOODS    BY  RESERVOIRS. 


135 


VOIR  ON  SAN  JOAQUIN  RIVER 
POWER  YIELD 

BY  RESERVOIR  OPERATING  DIAGRAM. 

Carried  out  on  a  Daily  Basis. 

mary,  see  Table  9a,  page  332.) 

Seasonal  irrigation  yield  1,800,000  acre-feet.     (Supplemented  by  ground  water 
supply  in  years  of  deficiency.     No  deduction  for  downstream  prior  rights). 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.P. 0.80. 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Friant — rain-water  flood.s,  10,700  sec.-ft:  snow-water  floods,  14,200  sec.-ft. 
Maximum  space  required  for  flood  control — rain-water  floods,  133,000  ac.-ft:  snow-water 
floods,  177.000  ac-ft. 

Stage  of 
reservoir 

at 
beginning 

of 
year  in 
acre-feet 

Irrigation 
draft  in 
acre-feet 

(no 
deduction 
for  down- 
stream 
prior 
rights) 

Evapora- 
tion in 
acre-feet 

Power 

draft 

through 

turbines 

in  acre-feet 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Wa,ste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

irrigation 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in 

feet 

Average 
power 

yield  in 

kilowatts 

(Load 

factor= 
1.00) 

Year 

797.100 

98.400 

791.100 

261.100 

713.700 

40.300 

51.000 

758.400 

587.100 

679.800 

589.400 

371.300 

48.700 

87.600 

86.300 

648,100 

436,600 

56,500 

1,800,000 
1,800  000 
1,800,000 
1.800.000 
1.686.900 

863.300 
1.800.000 
1.800.000 
1,800.000 
1,800,000 
1,800,000 
1.505.700 
1.320,700 
1.576.000 
1.800.000 
1.800,000 

844.300 
1,387,600 

13,700 
17,800 
16,500 
19.500 
10.200 
100 
18.600 
18.600 
19.400 
18,600 
14,600 
8,300 
2,400 
5.600 
15.000 
16,400 
1,900 
2,600 

1,699,100 

1,820,300 

1,868,200 

1,842,400 

1,510,300 

0 

1,821,400 

1,819,600 

1,838,500 

1,805,100 

1.800.000 

1.302.600 

420,900 

1.361.500 

1.652.700 

1.800,000 

536,400 

111,400 

0 

605,900 

401,300 

1,176,100 

0 

0 

357,900 

287,700 

644.200 

57,600 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

66,500 

74,600 

0 

0 

0 

0 

232,200 

69,200 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

113,100 

936,700 

0 

0 

0 

0 

0 

294,300 

479,300 

224,000 

0 

0 

955,700 

412,400 

488 
503 
506 
542 
454 
0 
510 
530 
544 
532 
466 
416 
329 
344 
443 
500 
394 
298 

73,800 
85,100 
86,200 
91,000 
60,900 
0 
86,400 
87,800 
90,300 
87,500 
77,700 
49,200 
12.300 
42,700 
69,300 
82,900 
17,800 
2,900 

1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 

28,984,500 
1,610,300 

219,800 
12,200 

25,010.400 
1,389,500 

3,530,700 
196,100 

442,500 
24,600 

3,415,500 
189,700 

484 

61,400 

Total 
Average 

9—52411 


13(5 


WATER   RESOURCES   OP    CALIFORNIA. 


TABLE  10.     TEMPERANCE  FLAT  RESER 

COMPARISON  OF  WATER 

FOR 

TWO  METHODS  OF 

Yearly  Summary  of  Computations 

(For  corresponding  monthly  sum 


Height  of  dam  595  feet. 

Capacity  of  reservoir  1,071,000  acre-feet. 


Run-off 

at 
Friaiit 

in 
acre-feet 

Flood  control  by  reservoir  operating  diagram 

Maximum  controllci  flow  at  Friant— rain-water  floods.  10,700  sec.-ft.; 

snow-water  floods,  14,200  sec.-ft. 
Maximum  reservoir  space  required — rain-water  floods,  133.000  ac.-ft.; 

snow-water  floods,  177,000  ac.-ft. 

Year 

Stage  of 
reservoir 

at 

beginning 

of 

year  in 

acre-feet 

Irrigation 

draft 

in 

acre-feet 

(no 
deduction 
for  down- 
stream 
prior 
rights) 

1,800,000 
1,800,000 
1,800,000 
1,800,000 
1,686,900 

863,300 
1,800,000 
1,800,000 
1,800,000 
1,800,000 
1,800,000 
1,505,700 
1,320,700 
1,576.000 
1,800,000 
1,800,000 

844,300 
1,387  600 

Evapora- 
tion in 
acre-feet 

Power 

draft 

through 

turbines 

in 
acre-feet 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

irrigation 

supply 

in 
acre-feet 

Average 
power 
head 
through 
period 

of 
operation 
in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 

1,115,000 
3,136,700 
1,825,500 
3,562,200 
1,023,700 

874,100 
2,905,300 
1,954,600 
2,827,000 
1,860,100 
1,596,500 
1,191.400 
1,362,000 
1,580,300 
2,376,800 
1,604,900 

406,100 
1,413,400 

797,100 

98,400 

791,100 

264,100 

713,700 

40,300 

51,000 

758,400 

587,100 

679,800 

589,400 

371,300 

48,700 

87,600 

86,300 

048,100 

436.600 

56,500 

13,700 
17.800 
16,500 
19,500 
10,200 
100 
18,600 
18,600 
19,400 
18,600 
14,600 
8.300 
2.400 
5,600 
15,000 
16,400 
1,900 
2.600 

1,699,100 

1.820,300 

1,868,200 

1,842,400 

1.510,300 

0 

1,821,400 

1,819,600 

1,838.500 

1,805,100 

1,800,000 

1.302,600 

420.900 

1,361,500 

1,652,700 

1,800.000 

536,400 

111,400 

0 

605,900 

401,300 

1,176,100 

0 

0 

357,900 

287,700 

644.200 

57,600 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

66,500 

74,600 

0 

0 

0 

0 

232,200 

69,200 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

0 

113,100 

936,700 

0 

0 

0 

0 

0 

294,300 

479,300 

224,000 

0 

0 

955.700 

412,400 

488 
503 
506 
542 
454 
0 
510 
530 
544 
532 
466 
416 
329 
344 
443 
500 
394 
298 

73,800 
85,100 
86,200 
91,000 
60,900 
0 
86,400 
87,800 
90.300 
87,500 
77,700 
49,200 
12,300 
42,700 
69,300 
82,900 
17,800 
2,900 

Total 
Average 

32.675,600 
1.815,300 

28.984,500 
1,610,300 

219,800 
12,200 

25,010,400 
1,389,500 

3,530,700 
196,100 

442,500 
24,600 

3,4)5,500 
189.700 

484 

61,400 

THE  CONTROL  OF  FLOODS  BY  RESERVOIRS. 


137 


VOIR  ON  SAN  JOAQUIN  RIVER. 
AND  POWER  YIELD 


FLOOD  CONTROL 

Carried  out  on  a  Daily  Basis. 

mary,  see  Table  10a,  page  342.) 

Seasonal  irrigation  yield  1,800,000  acre-feet.     (Supplemented  by  ground  water 
supply  in  years  of  deficiency.     No  deduction  for  downstream  prior  rights). 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.P.  =0.80. 


Flood  control,  holding  maximum  reservoir  space  required  (rain-water  floods  133,000  ac.-ft., 
snow-water  floods  177,000  ac.-ft.)  in  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Friant — rain-water  floods.  1 0,700  sec-ft;  snow-water  floods,  14,200  sce.-ft. 

Stage  of 
reservoir 

at 
beginning 

of 
year  in 
acre-feet 

Irrigation 

draft 

in 

acre-feet 

(no 
deduction 
for  down- 
stream 
prior 
rights) 

1,800,000 
1,800,000 
1,800,000 
1,800,000 
1,676,500 

863,300 
1,800,000 
1,800,000 
1,800,000 
1,800,000 
1,800,000 
1,336,800 
1,320,700 
1.576.000 
1,800,000 
1,800.000 

744.200 
1,387,600 

Evapora- 
tion in 
acre-feet 

Power 

draft 

through 

turbines 

in 
acre-feet 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 
in 

irrigation 
supply 

in 
acre-feet 

.Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

kilDwatts 
(Load 

factor= 
1.00) 

Year 

797,100 

98,400 

661,100 

244,900 

703,100 

40.300 

51.000 

609,300 

465.800 

555,600 

413,800 

199,000 

48,700 

87.600 

86,300 

545.700 

335,700 

56,500 

13,700 
16,500 
10,000 
19,300 
10,000 
100 
17,500 
16,700 
18,000 
16,500 
11,300 
4,900 
2,400 
5,600 
13,800 
14,900 
1,100 
2,600 

1,699,100 

1,833,000 

1,848,200 

1,847,100 

1,494,600 

0 

1  832,100 

1,823,000 

1.862,900 

1,815,900 

1,662,100 

1,100,500 

420,900 

1,361,500 

1,664,900 

1.800.000 

313,900 

111,400 

0 

724,500 

377.500 

1,237,600 

0 

0 

497,400 

258,400 

852,100 

169,500 

0 

0 

0 

0 

91,400 

0 

0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
4,200 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 

U 

0 

0 

123.500 

936,700 

0 

0 

0 

0 

0 

463,200 

479,.300 

224,000 

0 

0 

1,055.800 

412,400 

488 
488 
496 
536 
454 
0 
495 
503 
522 
498 
423 
357 
329 
344 
431 
473 
378 
298 

73,800 
83,700 
83,900 
90,600 
59,900 
0 
85,000 

s-'.eoo 

89,000 
83,700 
64.600 
35,500 
12,300 
42,700 
68,200 
79,000 
10.100 
2.900 

1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 

28,705  100 
1,594,700 

200,900 
11,200 

24,491,100 
1.360,600 

4,208,400 
233,800 

4,200 
200 

3,694,900 
205,300 

467 

58,300 

Total 
.\verage 

138 


WATER  RESOURCES   OF    CALIFORNIA. 


TABLE  11.     TEMPERANCE  FLAT  RESERVOIR  ON  SAN  JOAQUIN  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  YEARS 

BOTH 
WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  9  and  10. 

(For  correspHDnding  monthly  summary,  see  Table  11a,  page  352.) 

Height  of  dam  595  feet.  Capacity  of  reservoir  1,071,000  acre-feet. 

Seasonal  irrigation  yield,  1,800,000  acre-feet.    (Supplemented  by  ground  water 
supply  in  years  of  deficiency.    No  deduction  for  downstream  prior  rights). 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.F.  =  0.80. 


Year 

Without  flood  contro 

Coordinated  with  flood  control  by 
reservoir  operating  diagram 

Maximum  controlled  tiow  at 
Friant — rain-water  floods, 
10,700  sec.-ft.;  snow-water 

floods,  14,200  sec.-ft. 

Maximum  reservoir  space 

required — rain-water  floods, 

133.000  ac.-ft.;  snow-water 

floods,  177,000  ac.-ft. 

Flood  control,  holding  maximum 

reservoir  space  required  (rain-water 

floods,  133,000  ac.-ft.;  snow-water 

floods,  177,000  ac.-ft.)  in  reserve 

throughout  flood  season 

Maximum  controlled  flow  at 

Friant— rain-water  floods. 

1 0,700  sec.-ft. ;  snow-water 

floods,  14.200  sec.-ft. 

Irrigation 
draft  in 
acre-feet 

(no 
deduction 
for  down- 
stream 
prior 
rights) 

Deficiency 

in 

irrigation 

supply 

in 
acre-feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor = 
1.00) 

Irrigation 
draft  in 
acre-feet 

(no 
deduction 
for  down- 
stream 
prior 
rights) 

Deficiency 

in 

irrigation 

supply 

in 
acre-feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

Irrigation 
draft  in 
acre-fett 

(no 
deduction 
for  down- 
stream 
prior 
rights) 

Deficiency 

in 

irrigation 

supply 

in 
acre-feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 

1,800,000 
1,800,000 
1,800.000 
1,800,000 
1,686,900 

863,300 
1.800,000 
1,800,000 
1,800,000 
1,800,000 
1,800,000 
1,505,700 
1,320,700 
1,576,000 
1,800,000 
1,800,000 

844,300 
1,387,600 

0 

0 

0 

0 

113,100 

936,700 

0 

0 

0 

0 

0 

294,300 

479,300 

224,000 

0 

0 

955,700 

412,400 

73,800 
85.800 
91.100 
91,900 
60,900 
0 
86,600 
88,700 
93,500 
88,100 
77,700 
49,200 
12,300 
42,700 
69,300 
82  900 
17;800 
2,900 

1,800,000 
1,800.000 
1,800.000 
1,800,000 
1,686,900 

863,300 
1,800,000 
1,800,000 
1,800,000 
1,800,000 
1,800,000 
1,505,700 
1,320,700 
1,576,000 
1,800,000 
1,800,000 

844,300 
1,387,600 

0 

0 

0 

0 

113,100 

936,700 

0 

0 

0 

0 

0 

294,300 

479,300 

224.000 

0 

0 

955,700 

412,400 

73,800 
85,100 
86.200 
91,000 
60.900 
0 
86,400 
87.800 
90,300 
87,500 
77,700 
49,200 
12,300 
42,700 
69,300 
82,900 
17,800 
2,900 

1.800,000 
1.800,000 
1.800,000 
1,800,000 
1,676,500 

863,300 
1,800.000 
1,800,000 
1,800,000 
1,800,000 
1,800,000 
1,336,800 
1,320,700 
1,576.000 
1,800,000 
1,800,000 

744,200 
1,387,600 

0 

0 

0 

0 

123,500 

936,700 

0 

0 

0 

0 

0 

463.200 

479,300 

224,000 

0 

0 

1,055,800 

412,400 

73,800 
83,700 
83,900 
90,600 
59.900 
0 
85,000 
84,600 
89.000 
83.700 
64,600 
35.500 
12,300 
4:,700 
68.200 
79.000 
10,100 
2.900 

Total 
Average 

28,984,500 
1,610,300 

3,415.500 
189,700 

62,000 

28,984,500 
1,610,300 

3.415,500 
189,700 

61,400 

28,705,100 
1,594,700 

3,694.900 
205,300 

58,300 

San   Gabriel    Reservoir  on  the  San  Gabriel    River. 

The  ' '  Coordinated  Plan "  *  in  southern  California  contemplates  the 
construction  of  reservoirs  on  all  streams  of  suitable  terrain  for  joint 
operation  in  controlling  floods  and  conserving  water  now  unused.  It 
provides  on  each  stream,  to  the  extent  desirable  and  to  tlie  extent  that 
physical  conditions  permit,  for  tlie  coordination  of  flood  control  with 
irrigation  and  municipal  supply  through  both  surface  and  underground 
storage.     It  i)r()p()ses,  whorevcr  possible,  that  flood  control  be  coordi- 

•  See  Bui.  No.  12,  "Summary  Report  on  the  Water  Re.«iourccs  of  California  and  a 
Coordinated  Plan  for  their  Development, "  Division  of  Engineering  and  Irrigation, 
State  Department  of  Public  Works. 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  139 

iiatecl  witli  the  charging  of  the  undergroiuid  basins,  from  which  such 
a  large  part  of  local  supplies  are  obtained,  with  practically  the  entire 
unused  seasonal  run-off.  The  irregularly  occurring  flood  waters  would 
be  reduced  by  surface  reservoirs  to  flows  of  a  workable  size  for  intro- 
ducing into  the  subterranean  basins  but  the  principal  storage  of  water 
for  equalizing  the  intermittent  run-off  would  be  in  the  large  natural 
underground  basius  on  the  lower  reaches  of  the  streams  wherever  they 
are  available.  In  their  natural  state,  flood  waters  rusli  down  the  chan- 
nels in  volumes  too  large  for  complete  absorption  by  the  underground 
basins  even  with  extensive  spreading  Avorks.  By  reducing  these  flood 
flows  through  reservoir  control,  practically  their  entire  volume  may  be 
introduced  into  the  underground  basins  either  through  absorption  by 
the  natural  stream  channels  or  by  artificially  prepared  spreading  works. 
This  water  may  then  be  pumped  from  wells  penetrating  the  subter- 
ranean basins  at  such  times  and  for  such  purposes  as  necessity  demands. 
It  is  available  for  useful  purposes  in  the  same  way  that  most  of  the 
local  .supplies  in  southern  California  are  now  obtained.  In  some 
instances,  it  may  be  a  matter  of  economy  to  take  part  of  the  additional 
water  made  available  through  the  construction  of  surface  storage, 
directly  from  the  reservoir  without  incurring  the  expense  of  sinking 
it  underground  and  pumping  it  out  again.  Reservoir  operation  under 
the  "Coordinated  Plan,"  therefore  involves  all  or  in  part,  the  control 
of  floods,  the  temporary  storage  of  flood  water  to  be  released  later  at  a 
convenient  time  and  rate  for  sinking  underground,  and  the  equaliza- 
tion of  some  of  the  run-off'  between  seasons  for  an  independent  surface 
supply.  A  description  of  this  plan  for  southern  California  is  con- 
tained in  Bulletin  No.  17,  "The  Coordinated  Plan  of  Water  Develo])- 
ment  in  Southern  California." 

The  method  devised  by  the  "Coordinated  Plan"  for  operating  sur- 
face reservoirs  in  southern  California  in  order  to  secure  the  greatest  use 
of  their  capacity  for  both  flood  control  and  conservation  is  illustrated 
in  the  following  pages.  The  San  Gabriel  River  is  employed  for  this 
purpose  through  the  exemplary  use  of  the  San  Gabriel  reservoir.  This 
river,  in  having  the  longest  record  *  of  daily  flow,  is  found  to  be  the 
most  favorable  of  large  southern  California  streams  for  an  analysis 
of  the  characteristics  of  flood  floAV  and  is  so  used  in  the  previous 
chapters.  The  San  Gabriel  reservoir  extends  up  the  east  and  west 
branches  of  the  San  Gabriel  River  from  its  dam  site  which  is  imme- 
diately below  the  forks  and  eight  miles  up  the  canyon  from  tlie  edge  of 
the  valley  floor.  The  reservoir  is  proposed  for  construction  by  the  Los 
Angeles  County  Flood  Control  District.  Since,  at  the  time  of  preparing 
this  text,  the  desirable  capacity  for  this  reservoir  is  still  under  discus- 
sion, two  capacities  are  employed  in  the  illustrations,  one  180,000  and 
the  other  240,000  acre-feet.  These  correspond  to  dam  heights  of  383 
and  425  feet,  respectively. 

Capacity  as  large  as  these  is  not  necessary  for  flood  x)rotection  alone. 
The  removal  of  the  flood  menace  requires  only  that  flow  be  limited  to 
an  amount  that  will  pass  down  the  river  channel  without  endangering 
life  or  inflicting  serious  property  damage.     Flows  exceeding  10,000 

*  The  Santa  Ana  has  a  record  almost  as  long  as  the  San  Gabriel  River,  but  part 
for  the  1916  flood  is  missing.  This  makes  it  less  suitable  for  the  purpose  at  hand 
than  the  San  Gabriel  River  since  1916  is  the  largest  flood  year  of  the  period  of 
measurement. 


140  WATER    RESOURCES    OF    CALIFORNIA. 

second-feet  *  liave  passed  to  the  ocean  without  serious  difficulty  within 
the  last  several  years.  Exclusive  of  s))ace  that  should  be  i)rovided  for 
the  accumulation  of  silt  and  debris,  the  limitation  of  floods  to  10,000 
second-feet  requires  only  75,000  acre-feet  of  reservoir  capacity.  Simi- 
larly, 52,000  acre-feet  is  sufficient  to  limit  flood  flows  to  15,000  second- 
feet  (see  p.  61).  Capacity  in  excess  of  these  amounts,  employed  for 
limiting  floods  to  more  convenient  sizes,  is  essentially  useful  in  con- 
.serving  water  that  would  otherwise  waste  into  the  ocean.  It  makes 
possible  the  sinking  of  greatc^r  portions  of  the  total  run-off  into  the 
underground  basins  than  could  be  done  with  flows  as  large  as  10,000 
or  15,000  second-feet.  The  illustrations  herein,  limit  flows  to  1900 
second-feet,  an  amount  that,  it  is  believed,  can  be  sunk  conveniently 
into  the  large  subterranean  basin  underlying  the  San  Gabriel  Valley. 

A  rule  for  operating  a  reservoir  on  the  San  Gabriel  River  that  will 
limit  floods  to  1900  second-feet,  is  developed  in  the  previous  chapters 
of  this  volume.  It  is  expressed  on  Plate  XXI,  "Reservoir  Operating 
Diagram  for  Controlling  Floods  on  the  San  Gabriel  River."  p.  88. 
It  would  limit  floods  at  Azusa,  including  the  maximum  of  record,  to 
1900  second-feet.  The  maximum  flood  of  record  on  the  San  Gabriel 
River  occurred  on  January  18,  1916.  and  discharged  40,000  second-feet. 
To  limit  this  and  even  larger  floods  to  1900  second-feet,  requires  the 
reservation  at  times  of  a  maximum  space  for  flood  control  of  181,000 
acre-feet. 

The  use  of  the  operating  diagram  on  Plate  XXI  for  controlling  floods 
by  a  reservoir  as  far  upstream  as  the  San  Gabriel,  slightly  exceeds  the 
technical  limits  of  its  application.  If  the  technical  limitations  were 
stricth'  adhered  to,  not  more  than  half  the  16  square  miles  of  drainage 
area  below  the  San  Gabriel  reservoir  but  tributary  to  the  Azusa  gaging 
station,  should  remain  uncontrolled  since  this  area  may  produce  floods 
at  long  intervals  about  double  the  desired  regulated  flow  of  1900  second- 
feet.  However,  the  only  consequence  of  applying  the  diagram  to  the 
San  Gabriel  reservoir  is  that  the  desired  maximum  flow  of  1900  second- 
feet  at  Azusa  will  be  exceeded  at  average  intervals  of  several  decades  by 
the  uncontrolled  run-off  originating  downstream  from  the  dam.  The 
probable  limit  in  the  rate  of  flow  at  Azusa  would  be  about  double  the 
desired  (|uantity,  hut  several  centuries  may  elapse  between  flows 
iipproacliing  such  uuignitude.  At  times  of  excess  flow  at  Azusa  the 
gates  at  the  dam  would  he  closed  if  opcn-ated  in  accord  with  the  reservoir 
operating  diagram.  The  excess  flow  would  all  originate  downstream 
from  the  reservoir. 

In  using  the  reservoir  operating  diagram  of  Plate  XXI  for  limiting 
the  maximum  flow  to  1900  second-feet,  only  131,000  acre-feet  of  the 
total  capacity  of  the  San  Gabriel  reservoir  need  be  employed  for  this 
puri)ose.  A  diagram  could  be  constructed  that  would  employ  a  greater 
cai)acity  and  regulate  the  flow  to  less  than  1900  second-feet,  however, 
if  applied  to  the  San  Gabriel  reservoir,  the  desired  regulated  flow,  if 
made  much  less  than  1900  second-feet,  would  be  exceeded  ratlier  fre- 
(juently  by  the  run-off  from  the  drainage  area  downstream  from  the 
dam.  If  the  maximum  flood  control  reserve  were  increased,  say  to 
160,000  acre-feet,  the  flow  might  be  limited  to  1000  second-feet  at 
Azusa  exce])t  at  the  times  the  drainage  area  betweei^the  dam  site  and 

•  The  crest  discharge  at  Azusa  was  8,680  second-feet  on  March  7,  1918,  22,300 
second-feet  on  December  19,   1921,  and  11,600  second-feet  on  February  9,   1922. 


THE  CONTKOIi  OF  FLOODS  BY  RESERVOIRS.  141 

Azusa  produce.s  a  oreater  amount.  This  might  occur  every  few  years 
but  the  accumulated  duration  of  flows  in  excess  of  1000  second-feet 
would  be  reduced  and  less  effort  would  be  required  in  sinking  the  water 
into  the  underground  basin.  However,  since  it  is  believed  that  flows 
approximating  1900  second-feet  may  be  made  to  percolate  into  the 
underground  basin  at  a  cost  small  in  com})arison  with  that  of  29,000 
acre-feet  of  additional  reservoir  capacity,  1900  second-feet  was  selected 
as  a  suitable  regulated  flow  for  illustrating  the  principles  of  coordinat- 
ing flood  control  and  conservation  in  the  same  reservoir. 

The  reservoir  operating  diagram,  in  addition  to  securing  the  control 
of  floods  through  the  reservation  of  adequate  space  at  all  times  for 
temporarily  detaining  excess  flow  that  might  occur  under  the  circum- 
stances then  existing,  accomplishes  the  storage  of  water  in  amounts 
varying  with  the  season.  Through  holding  in  reserve  only  the  space 
required  for  the  control  of  floods  that  may  occur  under  existing  circum- 
stances and  releasing  this  reserve  immediately  as  the  possibility  of  its 
need  for  flood  control  has  passed,  run-off  may  be  stored  in  the  part 
of  the  maximum  flood  control  reserve  not  required  at  that  time  for  flood 
control.  In  this  way  during  many  seasons,  considerable  volumes  of 
stored  water  are  accumulated  without  the  use  of  reservoir  space 
other  than  that  included  in  the  maximum  flood  control  reserve,  and 
tliis  is  done  without  jeo])ardizing  the  certainty  of  the  control  effected. 
The  water  so  stored  may  be  draw^n  from  the  reservoir  at  whatever  rate 
and  time  desired  during  the  season  of  its  detention.  Should  it  be  held 
into  the  next  flood  season,  it  is  subject  to  release  as  flood  control  water 
if  the  space  occupied  by  it  is  needed  in  the  flood  control  reserve. 

Where  the  reservoir  capacity  exceeds  the  maximum  flood  control 
reserve  required  by  the  diagram,  as  in  the  illustrations  herewith,  the 
excess  capacity  may  be  employed  either  for  the  seasonal  or  over-year 
storage  of  water.  If  employed  for  seasonal  storage,  its  yield  will  be  of 
the  same  character  as  the  water  stored  seasonally  in  the  unused  part  of 
the  maximum  flood  control  reserve  and  will  augment  the  (piantity  of 
stored  water  available  in  irregular  amounts  from  season  to  season.  If 
employed  for  ovei'-year  storage,  its  yield  may  be  drawn  from  the 
reservoir  in  uniform  amounts  through  all  .seasons  and  so  constitute  an 
independent  surface  supply  that  does  not  require  auxiliary  sources 
during  seasons  of  deficient  run-oft'.  Thus  the  yield  of  reservoirs  under 
the  ''Coordinated  Plan"  may  be  divided  into  three  parts,  namely,  the 
variable  flow  of  limited  size  that  occurs  during  the  winter  and  spring 
months  as  a  result  of  the  flood  control  operations,  the  seasonally  stored 
water  that  may  be  drawn  from  the  reservoir  at  any  desired  rate  and 
time  during  the  summer  and  fall  of  the  year  of  its  detention,  and  the 
flow  equalized  between  seasons  that  may  be  drawn  off  at  a  uniform  rate 
year  in  and  year  out.  The  yield  of  the  first  class,  in  passing  down  the 
channel  in  flows  of  limited  size  but  at  the  time  of  natural  run-off,  is 
controlled  in  volume  of  flow  only,  while  that  of  the  second  and  third 
class,  in  being  stored  water,  is  controlled  both  in  time  and  volume. 
The  yield  of  all  three  classes  is  useful.  The  fir;  t,  arriving  in  the  winter 
and  spring  in  flows  of  limited  si/.e,  may  be  sunk  undefgi-ound  as  it 
occurs.  The  second,  in  being  stored  water,  may  be  drawn  from  the 
reservoir  as  convenient  either  for  sinking  underground  or  for  supple- 
menting surface  supplies.     It  being  of  irregular  amount  from  season 


142  WATER  RESOURCES   OF    CALIFORNIA. 

to  season  Jiiid  in  some  seasons  tluTc  ])t'in<»'  none  at  all,  tlie  yiekl  of  the 
second  class  can  not  become  an  indc])eii<l('nt  source  of  supjily  without 
further  e({ualizati()n  in  an  undei'irround  basin.  The  yield  of  the  third 
class,  in  bein<r  ecjualized  between  seasons,  nuiy  constitute  an  indepen- 
dent surface  supply. 

These  three  classes  into  which  the  yield  may  be  divided,  tojrether  with 
the  water  passed  for  prior  rio:hts  and  evaporated  from  the  reservoir 
surface,  include  the  entire  surface  run-off  of  the  stream.  Reservoir 
capacity  just  (Mpial  to  the  recpiired  maximum  flood  control  reserve  Avill 
convert  the  entire  mean  seasonal  run-off  into  yield  of  the  first  two 
classes.  CajHicity  in  addition  to  this  either  changes  part  of  the  yield 
of  the  first  class  to  yield  of  the  second  class  or  from  the  first  two 
classes  to  the  third,  according  as  the  space  in  excess  of  the  maximum 
flood  control  reserve  is  employed  for  seasonal  or  over-year  storage.  On 
streams  having  a  large  subterranean  basin  on  their  lower  courses,  the 
total  useful  yield  of  a  reservoir  can  not  be  increased  by  enlarging  the 
capacity  to  an  amount  exceeding  the  maximum  flood  control  reserve 
required  to  control  flows  to  a  size  that  may  be  completely  sunk  into  the 
underground  basin.  The  function  of  additional  reservoir  capacity  is 
limited  to  making  the  water  available  more  conveniently  either  in 
smaller  flows  or  at  special  times  of  the  year. 

Analyses  were  made  of  the  80  years  of  stream  flow  record  on  the  San 
(labriel  Kiver  to  determine  the  yield  of  the  >San  Gabriel  reservoir  under 
several  modes  of  operation.  In  these  tests  it  is  assumed  that  the  reser- 
voir was  in  existence  at  the  beginning  of  the  period  and  was  operated 
through  the  succeeding  30  years  as  described  in  the  several  instances. 
The  destruction  of  reservoir  capacity  by  the  accumulation  of  silt  and 
de])ris  is  neglected  and  the  first  152  second-feet  of  natural  flow  are 
l)assed  for  ])rior  rights.  The  water  passed  for  prior  rights  in  all  modes 
of  reservoir  operation  and  for  all  reservoir  capacities  constitutes  40.5 
per  cent  of  the  total  surface  run-oif  of  the  i)eriod  of  analysis. 

The  application  of  the  reservoir  operating  diagram  hei'ein  described 
to  the  daily  flows  throughout  the  oO-year  period  of  record,  results  in 
the  average  yield  on  the  part  of  the  maximum  flood  control  reserve 
which  is  the  first  l:n.000  acre-feet  of  capacity,  of  37.100  acre-feet  per 
season  during  the  winter  and  spring  months  in  flows  controlled  to  less 
than  1900  second-feet  and  of  36.700  acre-feet  i)er  season  in  seasonally 
stored  water  that  may  be  drawn  from  the  reservoir  as  desired  within 
the  year  of  its  detention.  These  yields  are  29.6  and  29.2  per  cent 
respectively  of  the  average  run-off  for  the  period.  Some  water  is  stored 
in  27  of  the  30  seasons  analyzed  but  in  no  season  is  the  entire  131,000 
acre-feet  filled.  The  nearest  to  filling  is  in  1907  when  110,300  acre-feet 
are  held  in  storage.  This  reservoired  water,  in  being  stored  witli  facili- 
ties required  to  secure  the  desired  limit  to  flood  flows  of  1900  second- 
feet,  is  held  without  extra  expense.  Together  with  the  winter  and 
spring  controlled  flows  resulting  from  flood  regulation,  it  constitutes 
the  entire  run-off  from  the  San  Gabriel  watershed  tributary  to  Azusa, 
with  the  exception  of  the  water  passed  for  prior  rights  and  evaporated 
from  the  res(M"voii"  surface. 

Wifli  a  capacify  of  ISO.OOO  jicre-feel,  the  space  in  excess  of  the  maxi- 
mum flood  control  resei-ve  (131,000  aci-e-feet),  if  employed  for  seasonal 
storage  in  conjunction  with  flood  control,  would  convert  17,400  acre- 


THE  CONTROL  OP  FLOODS  BY  RESERVOIRS.  143 

feet  of  tlie  average  winter  and  sprino-  yield  in  controlled  flows  of  the 
maximmn  flood  control  reserve,  into  17,100  acre-feet  of  seasonally 
stored  water.  On  an  average  about  300  acre-feet  per  season  would  be 
lost  by  evaporation  in  doing-  this.  Similarly,  with  a  capacity  of  240,000 
acre-feet,  the  space  in  excess  of  the  maximum  flood  control  reserve 
(131,000  acre-feet)  would  convert  28,800  acre-feet  of  the  average 
winter  and  spring  yield  in  controlled  flows  of  the  maximum  flood  con- 
trol reserve,  into  28,400  acre-feet  of  seasonally  stored  water.  About 
400  acre-feet  per  season  would  be  lost  by  evaporation  on  the  average  in 
doing  this.  These  yields  are  13.6  and  22.6  per  cent  respectively  of  the 
average  run-off  of  the  30-year  period.  Thus,  in  a  capacity  of  180,000 
acre-feet,  the  49,000  acre-feet  additional  to  the  maximum  flood  control 
reserve  would  convert  on  an  average  17.100  acre-feet  of  yield  controlled 
only  in  volume,  to  yield  controlled  both  in  time  and  volume  or  one  acre- 
foot  for  each  2.9  acre-feet  of  storage  capacity.  In  a  capacity  of  240,000 
acre-feet,  the  60,000  acre-feet  additional  to  180,000  acre-feet,  would 
similarly  convert  on  an  average  11,300  acre-feet  per  season  from  flow 
controlled,  only  in  volume  to  flow  controlled  both  in  time  and  volume, 
or  one  acre-foot  for  each  5.3  acre-feet  of  storage  capacity. 

If  the  capacity  in  excess  of  the  maximum  flood  control  reserve  of 
131,000  acre-feet  were  employed  for  over-year  instead  of  seasonal 
storage  in  conjunction  with  flood  control,  a  uniformly  continuous 
supply  of  22  second-feet  or  15,900  acre-feet  per  season  could  be  drawn 
from  a  capacity  of  180,000  acre-feet.  Similarlj^,  a  uniformly  con- 
tinuous supply  of  32*  second-feet  or  23,300  acre  feet  per  season  could 
be  drawn  from  a  capacity  of  240,000  acre-feet.  These  yields  are  12.7 
and  18.6  per  cent,  respectively,  of  the  average  run-off  of  the  30-year 
period.  In  both  instances  this  Avater  would  be  derived  from  the  winter 
and  spring  controlled  flows  and  the  seasonally  stored  water  of  the 
maximum  flood  control  reserve.  Thus,  in  a  capacity  of  180,000  acre- 
feet,  the  49,000  acre-feet  additional  to  the  maximum  flood  control 
reserve  w^ould  convert  3300  acre-feet  per  season  controlled  only  in 
volume  together  M'ith  14,000  acre-feet  controlled  both  in  time  and 
volume  but  not  equalized  between  seasons,  into  15,900  acre-feet  per 
season  controlled  both  in  time  and  volume  and  equalized  between  the 
years,  or  one  acre-foot  per  season  brought  under  complete  control  for 
each  3.1  acre-feet  of  additional  capacity.  On  an  average  about  1400 
acre-feet  per  season  would  be  lost  by  evaporation  in  doing  this.  In  a 
capacity  of  240,000  acre-feet,  the  60,000  acre-feet  additional  to  the 
180,00()  acre-feet  would  similarly  convert  11,600  acre-feet  per  season 
controlled  only  in  volume  into  10,600  acre-feet  per  season  controlled 
in  both  time  and  volume,  of  which  7400  acre-feet  per  season  would  be 
equalized  between  seasons,  or  one  acre-foot  per  season  brought  under 
control  as  to  time  for  each  5.7  acre-feet  of  additional  storage  capacity. 

*  In  the  analyses  of  reservoir  yield  for  the  period  of  measured  run-off,  Tables  13 
and  IZa,  a  yield  of  41  second-feet  continuous  flow  is  obtained  from  Jan.  1,  1897,  to 
Oct.  1,  1926,  with  a  draft  of  61,300  acre-feet  on  water  stored  in  the  reservoir 
prior  to  the  beginning  of  the  period.  At  the  time  of  making  the  computations,  it 
was  thought  that  the  rainfall  of  the  seasons  just  prior  to  Jan.  1,  1897,  would  yield 
this  extra  water  .so  that  41  second-feet  would  be  the  long  time  average  yield;  how- 
ever, subsequent  detail  study  of  rainfall  records  indicates  that  it  is  improbable  that 
so  large  an  amount  of  extra  water  would  have  accumulated  during  the  seasons  just 
prior  to  189  7,  but,  sufficient  would  probably  have  accumulated  to  increase  the  yield 
considerably  over  that  for  the  exact  period  of  analyses.  The  exact  yield  in  con- 
tinuous flow  for  the  period  Jan.  1,  1897,  to  Oct.  1,  1926,  is  32  second-feet  or  23,300 
acre-feet  per  season. 


144  WATER   RESOURCES   OF    CALIFORNIA. 

On  an  averafro  about  1000  acre-feet  per  season  would  be  lost  by  evap- 
oration in  (loinp:  this. 

The  three  following  tables  summarize  the  yield  of  180.000  and  240.- 
000  acre-feet  of  capacity  operated  in  accordance  with  the  "Coordinated 
Plan"  and  compare  it  with  the  yield  of  the  maximum  flood  control 
reserve  if  not  employed  in  conjunction  with  additional  capacity.  The 
first  two  tabulate  the  averapre  run-off  divided  between  the  yield  in  prior 
rights  water,  controlled  flows  resulting  from  flood  regulation,  seasonally 
stored  water,  continuous  uniform  flow  equalized  between  seasons  by 
over-year  storage,  and  evaporation  loss  from  the  reservoir  surface.  The 
first  table  assumes  that  the  space  in  addition  to  the  maximum  flood 
control  reserve  is  employed  for  seasonal  storage  in  conjunction  with 
the  flood  control  ojierations  and  the  second  table  for  over-year  storage. 
The  third  table  further  segregates  the  yields  of  the  first  two  tables 
according  to  the  size  of  total  flows  passing  Azusa.  Still  further  detail 
is  printed  in  the  tables  of  yearly  summaries  at  the  end  of  this  section 
and  in  the  tables  of  monthly  summaries  in  Chapter  YIII.  The  actual 
computations  were  carried  out  on  a  daily  basis  to  meet  the  requirements 
of  the  reservoir  operating  diagram  which  calls  for  a  daily  adjustment 
of  reservoir  level  during  the  flood  .season.  The  daily  computations  are 
too  voluminous  to  place  in  print. 

It  may  be  observed  on  reviewing  the  three  following  tables  that  the 
juaximum  flood  control  reserve,  without  additional  capacity,  controls 
all  floods  and  renders  the  entire  run-off  of  the  stream,  except  for  0.7 
per  cent  loss  by  evaporation,  available  for  sinking  undersrround.  It 
yields  29.2  per  cent  of  the  average  run-off  in  seasonally  stored  water 
but  does  not  create  an  independent  surface  supply.  The  two  larger 
capacities  employed  for  flood  control  and  seasonal  storage,  control  all 
floods  and  render  the  entire  run-off,  excejit  for  slightly  larger  evapora- 
tion losses,  available  for  sinking  underground.  However,  a  larger  frac- 
tion of  the  average  run-off  is  made  available  as  seasonally  stoi-ed  water. 
The  two  larger  capacities  convert  42.0  and  51.9  per  cent,  respectively, 
of  the  average  run-oft*  into  seasonally  stored  water  instead  of  29.2  per 
cent,  the  yield  of  the  maximum  flood  control  reserve  without  addi- 
tional capacity.  In  so  rloing  the  two  larger  capacities  do  not  conserve 
more  water  but  rather  make  larger  portions  of  the  average  run-oft'  more 
conveniently  available.  When  employed  for  over-year  storage  in  con- 
junction with  flood  control,  the  two  larger  capacities  still  control  all 
floods  and  render  the  entire  run-off  of  the  stream  available  for  sinking 
underground  if  desired,  but  12.7  and  18.6  per  cent,  respectively,  of  the 
avei-age  run-oft'  is  in  a  uniformly  continuous  yield  suitable  for  direct 
diversion  from  the  reservoir  for  municipal  juirjioses.  The  losses  by 
evaporation  from  the  reservoir  surface  are  l.S  and  2.6  per  cent,  respec- 
tively, in  doing  this.  In  all  instances  40.5  per  cent  of  the  average  run-off 
passes  the  dam  to  satisfy  downstream  prior  surface  rights. 

In  size  of  total  flow  passing  Azusa,  the  maximum  flood  control 
reserve  yields  66.4  per  cent  of  the  average  run-off  in  flows  of  less  than 
500  seeond-feet  and  78.5  per  cent  in  flows  le.ss  than  1000  second-feet. 
The  two  larger  capacities  of  180,000  and  240,000  acre-feet,  employed 
for  flood  control  and  seasonal  storage,  yield  S5.7  and  93.5  per  cent  of 
their  water,  respectively,  in  flows  le.ss  than  1000  second-feet.  Employed 
for  flood  control  in  conjunction  with  over-year  storage,  180,000  acre- 


THE  CONTROL  OP  FLOODS  BY  RESERVOIRS.  145 

feet  of  capacity  would  yield  74.8  per  cent  of  the  averao'e  run-off  in 
flows  of  less  than  1000  second-feet.  Had  a  reservoir  operating  diagram 
been  constructed  to  limit  flows  to  1000  second-feet  instead  of  1900,  as  in 
the  foregoing  illustrations,  its  maximum  flood  control  reserve  of  160,- 
000  acre-feet  would  yield  over  99  per  cent  of  the  average  run-off  in 
flows  of  size  less  than  1000  second-feet.  For  a  total  capacity  of  180,000 
acre  feet,  the  division  of  the  yield  into  controlled  flows  and  seasonally 
stored  water,  however,  avouUI  be  diff'erent,  the  amount  of  the  seasonally 
stored  water  being  less. 


146 


WATER   RESOURCES   OF    CALIFORNIA. 


AVERAGE  WATER  YIELD  OF  SAN  GABRIEL  RESERVOIR 

UNDER  "COORDINATED  PLAN." 

FLOOD  CONTROL  AND  SEASONAL  STORAGE  COORDINATED 

January  1,  1897  to  October  1,  1926 

(For  yearly  values,  see  Table  12,  page  158.) 


Maximum  flood  control 

reserve  or  first  131,000 

acre-feet  of  capacity 

1 80,000  acre-feet  capacity 

240,000  acre-feet  capacity 

Item 

Acre-feet 
per  season 

Per  cent  of 
average 
seasonal 
run-off 

Acre-feet 
per  season 

Percent  of 
average 
seasonal 
run-off 

Acre-feet 
per  season 

Per  cent  of 
average 
seasonal 
run-off 

Passed  by  dam  for  prior  rights 
(first  152  second-feet  of  natural 
flow) 

50.900 

37,100 

36,700 

800 

40.5 

29.6 
29.2 
0.7 

.50,900 

19,700 

53,800 

1,100 

40.5 

15.7 

42.9 

0.9 

50.900 

8,300 

65,100 

1,200 

40.5 

Flood  controlwaterpassiog  Azusa 
during  flood  season  at  rates  less 

6.6 

51.9 

Evaporation  from  reservoirsurface 

1.0 

Total               

125,500 

100.0 

125,500 

100.0 

125,500 

100.0 

THE  CONTROL  OP  FLOODS  BY  RESERVOIRS. 


147 


AVERAGE  WATER  YIELD  OF  SAN  GABRIEL  RESERVOIR 

UNDER  "COORDINATED  PLAN." 

FLOOD  CONTROL,  SEASONAL  AND  OVER- YEAR  STORAGE 

COORDINATED 

January  1,  1897  to  October  1,  1926 

(For  yearly  values,  see  Table  13,  page  160.) 


Maximum  flood  control 

reserve  or  first  131,000 

acre-feet  of  capacity 

180,000  acre-feet  capacity 

240,000  acre-feetcapacity 

Item 

Acre-feet 
per  season 

Percent  of 
average 
seasonal 
run-ofE 

Acre-feet 
per  season 

Percent  of 
average 
seasonal 
run-off 

Acre-feet 
per  season 

Per  cent  of 
average 
seasonal 
nin-off 

Passed  by  dam  for  prior  rights 
(first  152  second-feet  of  natural 
flow) 

50,900 

37,100 
3b,700 

0 

800 

40.5 

29.6 
29.2 

0 

0.7 

50,900 

"33,800 
22,700 

15,900 

2,200 

40.5 

2fi.9 
18.1 

12.7 

1.8 

50,900 

'^22,200 
1^25,900 

1^23,300 

3,200 

40  5 

Flood  control waterpassingAzusa 
during  flood  season  at  rates  less 
than  1,900  second-feet 

17  7 

Seasonally  stored  water 

20  6 

Yield  in  a  uniformly  continuous 

18  6 

Evaporation  from  reservoir  sur- 
face   

2  6 

Total 

125,500 

100.0 

125,500 

100.0 

125,500 

100.0 

"The  average  yield  in  flood  control  water  shown  in  Tables  13  and  13afrom  which  this  summary  is  compiled, is  34,000 
acre-feet  per  season.  In  the  computations  for  these  tables,  the  period  of  analysis  closed  with  7,600  acre-feet  less  water 
in  storage  than  at  the  beginning.  This  water,  the  equivalent  of  200  acre-feet  per  season,  entered  storage  prior  to  the 
beginning  of  the  period  and  was  released  as  flood  control  water  during  the  first  year.  Therefore,  it  is  deducted  from  the 
average  yield  in  flood  control  watershown  in  Tables  13  and  13a  to  obtain  the  exact  yield  for  the  period  of  analysis. 

b  The  average  yield  in  flood  control  water,  seasonally  stored  water  and  uniformly  continuous  flow  shown  in  Tables 
13  and  13a  from  which  this  summary  is  compiled,  is  30,000,  13,800  and  29,700  acre-feet  per  season,  respectively.  In  the 
computations  for  these  tables  the  period  of  analysis  closed  with  61 ,300  acre-fee*  less  water  in  storage  than  at  the  beginning. 
This  water,  the  equivalent  of  2,060  aore-feet  per  season,  entered  storage  prior  to  the  beginning  of  the  period.  To  obtain 
the  exact  yield  for  the  period,  a  supplementary  analysis  was  made  having  the  same  amount  of  water  in  storage  at  the 
beginning  and  at  the  end  of  the  period.  This  gave  the  smaller  values  for  flood  control  water  of  22,200  acre-feet  per  season 
and  for  uniformly  continuous  flow  of  23,300  acre-feet  per  season,  and  the  larger  value  for  seasonally  stored  water  of 
25,900  acre-feet  pei  season,  entered  herein. 


148 


WATER   RESOURCES    OF    CALIFORNIA. 


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Stage-Flood  control  coondinated  wj 
and  variable  summer  draf 


J_J. 


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"^^^.BRiEL  River  Floods 


LEGEND 

I  control  alone.   Not  shown  where  coincident  with  othe 
— )    Ugn  the  reservoir  for  prior  rights. 

d  control  and  constant  draft  of  22  sec.  ft.    Natural  flow 
average)   released  in  flows  of  1900  sec.ft.  or  less  in  e> 

r  stage  for  flood  control.    Not  shown  where  coincident  Af-  I  Q  CC  F"P\/A|  D 

-Jfel>  for  flood  control,  constant  draft  of  22  sec.ft  and  var^  LOLrVUI  R 

JJ?'^e"V° l^^ ^^i'^^k  f^"^'^  through  Ihe  reservoir  forDninW  rnf)RniNATFn 

ess  of  constant  draft  and  water  passed  for  prior  rights '*^'^  kyUUnUII>ini  LU 

n  Gabriel  River  near  Azusa.  taken  from  records  of  UniteijSA    1,900  SELC.  FT. 

--  Gabriel  River  near  Azusa,  with  reservoir  operated  cof^-^''    ^^^-  '^^■ 

■00     AC.  FT 


1  ,1  -Ur^L^^';^'"^^'l-'^'[°'"  -'"]>  '  yP  ♦=  successive  dates  in  the; 
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L  J^  h  July  1, 1102  to  July  1, 1903,  February  1905  and  March  1909  a 


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iSSSWf,.'.: 


Effect  of  Controlling  San  Gabriel  River  Floods 
stage  of  san  gabriel  reservoir 

FLOOD  CONTROL  AND  CONSERVATION  COORDINATED 


THE  CONTROL  OF  FLOODS  BY  RESERVOIRS.  153 

Monthly  and  yearly  summaries  of  the  computations  from  which  the 
foregoing  tables  were  prepared  have  been  assembled,  together  with 
summaries  of  other  comparisons  made  in  studying  various  modes  of 
reservoir  operation.  The  yearly  summaries  follow  herewith  but  the 
monthly  summaries,  because  of  their  bulk,  are  placed  in  a  separate 
chapter.  Included  in  these  is  the  test  of  180,000  acre-feet  reservoir 
capacity  operating  as  proposed  in  the  "Coordinated  Plan"  except 
that,  instead  of  employing  the  reservoir  operating  diagram  to  grade 
the  flood  control  reserve  in  accord  with  current  necessities,  the  maxi- 
mum amount  of  131,000  acre-feet  was  held  empty  until  April  19th,  tlie 
close  of  the  flood  season.  With  over-year  storage,  this  change  reduced 
the  average  yield  in  seasonal  stored  water  from  22,700  to  3000  acre- 
feet  per  season,  a  reduction  of  87  per  cent.  It  also  reduced  the  yield 
in  uniformly  continuous  flow  from  15,900  to  13,000  acre-feet  per  season. 
Floods  would  have  been  limited  to  1900  second-feet  just  the  same. 

In  addition  to  the  water  yield,  these  computations  furnish  informa- 
tion upon  the  reservoir  stage  under  the  several  conditions  of  operation. 
Plate  XXVI,  "Effect  of  Controlling  San  Gabriel  River  Floods  upon 
the  Stage  of  the  San  Gabriel  Reservoir,"  delineates  the  reservoir  stage 
day  by  day  from  1896  to  1927  for  three  conditions  of  operation  repre- 
senting three  steps  in  coordinating  the  several  uses  of  180,000  acre- 
feet  of  reservoir  space ;  first,  operating  for  flood  control  alone  by  the 
reservoir  operating  diagram,  second,  operating  for  flood  control  in 
combination  with  a  constant  draft  from  over-year  storage,  and  tliird, 
completely  coordinating  the  usefulness  of  the  reservoir  space  by  operat- 
ing for  flood  control,  a  constant  draft  from  over-year  storage  and  a 
variable  summer  draft  from  seasonally  stored  water. 

Plate  XXVI  assumes  that  a  reservoir  of  180,000  acre-feet  capacity 
was  in  existence  in  1896  and  operated  through  subsequent  years  in 
accord  successively  with  each  of  the  three  conditions  of  operation 
above  mentioned.  The  volume  of  water  in  storage  expressed  in  acre- 
feet  is  shown  on  every  day  of  the  30-year  period  by  the  vertical  position 
on  the  reservoir  space  scale,  of  lines  extending  across  the  plate  in 
several  rows.  The  top  guide  line  of  each  row  represents  a  full  reservoir 
and  the  bottom  line  an  empty  reservoir.  The  space  between  each  pair 
of  horizontal  guide  lines  represents  20,000  acre-feet. 

The  light  red  line  delineates  the  reservoir  stage  were  it  operated  for 
flood  control  alone  by  releasing  water  only  as  required  by  the  reservoir 
operating  diagram.  The  heavy  black  line  delineates  the  reservoir  stage 
were  it  operated  for  flood  control  and  a  constant  draft  of  22  second- 
feet  from  over-year  storage.  The  heavy  red  line  delineates  the  reservoir 
stage  were  it  operated  coordinately  for  flood  control,  a  constant  draft 
of  22  second-feet  from  over-year  storage  and  a  variable  summer  draft 
from  the  seasonally  stored  water.  Below  the  reservoir  stage  lines  in 
each  row  is  shown  in  a  light  black  line  to  a  special  scale  superimposed 
upon  the  reservoir  stage  scale,  the  unimpaired  flow  of  the  river  at  Azusa 
and  in  a  light  red  line,  the  flow  as  controlled  by  the  coordination  of  flood 
control,  seasonal  and  over-year  storage.  A  line  of  black  dots  shows  the 
daily  value  of  the  progressive  rainfall  index  used  in  entering  the  reser- 
voir operating  diagram  to  determine  the  necessary  flood  control  reserve. 
The  following  table  shows  the  average  size  of  the  total  flow  passing 
Azusa  for  the  three  steps  in  coordinating  the  use  of  reservoir  space 
described  above. 

10— &2411 


154 


WATER   RESOURCES   OF    CALIFORNIA. 


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Flood  control  completely  coordinated  with  conservation 

Reservoir  emptied  each  summer  to  a  level  that  would 
maintain  constant  draft  through  critical  period,  con- 
stant draft  of  22  second-feet  maintained,  other  drafts 
only  as  required  by  reservoir  operating  diagram 
"Coordinated  Plan" 

Hi 

19,790 
16,680 
4,600 
1,290 
1,500 
660 

5        O 

Constant 
flow  from 
over-year 
storage  in 
acre-feet 
per  season 

o  oo  oooc 

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Seasonally 

stored 

water 

released 

as  a 
variable 
summer 
flow  in 
acre-feet 
per  season'' 

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Flood 
control 
water 
passing 
Azusa 
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acre-feet 
per  season  >■<■ 

190 
1,340 
1,380 
1,250 
1,550 

650 

1         CO 

Flood  control  partially  coordinated  with  conservation 

Constant  draft  of  22  second-feet  maintained, 

other  drafts  only  as  required  by 

reservoir  operating  diagram 

•SIS 
111 

15,160 
2,350 
3,240 
3,400 
3,510 
2,330 

3        O 
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Constant 
flow  from 
over-year 
storage 
in  acre-feet 
per  season 

oooo  ooc 
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Seasonally 

stored 

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released 

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summer 
flow  in 
acre-feet 
per  season 

oo  o  oooc 

>      o 

Flood 

control  water 

and  waste 

over 
spillway 
passing 
Azusa 
at  rates 
less  than 
1,900  second- 
feet  in 
acre-feet 
perseasonbe 

300 
2,100 
3,100 
3,300 
3,4,30 
2,290 

o 

CO 

Flood  control  alone 

Water  drawn  from  reservoir 

only  as  required  by  reservoir 

operating  diagram 

Jig 
^  S, 

740 
2,870 
3,820 
4,200 
4,000 
2,750 

o 
o 
o" 

Seasonally 

stored 

water 

released 

as  a 
variable 
summer 
flow  in 
acre-feet 
per  season 

oooo  o  oc 

o 

Flood 

control  water 

and  waste 

over 
spillway 
passing 
Azusa 
at  rates 
less  than 
1,900  second- 
feet  in 
acre-feot 
per  season" ' 

740 
2,870 
3,820 
4,200 
4,000 
2,750 

o 
o 
o" 

o 

1 

o 

o 

i 

o 

l 

1 

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THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


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THE   CONTROL   OF   FLOODS   BY   RESERVOIRS.  157 


SAN   GABRIEL    RESERVOIR   ON    SAN    GABRIEL    RIVER. 

Tables  of  Yearly  Summaries  of  Water  Yield  Computed  on  a   Daily   Basis. 

Showing  the  effect  of  coordinating  flood  conti'ol  ana  conservation. 

(See   Chapter   VIII   for   corresponding 

monthly   summaries.* ) 

Table  12 — Yield  under  "Coordinated  Plan,"  flood  control  and  seasonal  .storage 
coordinated.     Capacity  180,000  and  240,000  acre-feet. 

Tablk  1.3 — Yield  under  "Coordinated  Plan,"  flood  control  and  seasonal  and  over- 
year storage  coordinated.     Capacity  180,000  and  240,000  acre-feet. 

Table  14 — Average  size  of  flows  under  "Coordinated  Plan."  Capacity  180,000 
and  240,000  acre-feet. 

Table  15 — Comparison  of  yield  for  two  methods  of  flood  control.  Flood  control 
coordinated  with  seasonal  ana  over-year  storage.  Capacity  180,000 
acre-feet. 

Table  16 — Comparison  of  yield  for  three  steps  in  coordinating  the  use  of  reser- 
voir space.     Capacity  180,000  acre-feet. 

Table  17 — Comparison  of  yield  operating  for  flood  control  and  constant  draft 
only.     Capacity  180,000  and  240,000  acre-feet. 

Table  18 — Average  size  of  flows  for  throe  steps  in  coordinating  tlic  use  of  reser- 
voir space.     Capacity  180,000  acre-feet. 


♦Monthly  summaries  not  prepared  for  Table.s  14  and  IS. 


158 


WATER  RESOURCES   OF   CALIFORNIA. 


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55,685 

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100.310 

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187,233 

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80,172 

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26,836 

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159 


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THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


161 


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Flood  control  water  passing  Azusa 

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than  1,900  second-feet  in 

acre-feet 

Flood 
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and 

over-year 

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« 

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Maximum 
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or  first 
131.000 
acre-feet 
of  capacity 

■ 

THE   CONTROL   OP   FLOODS   BY   RESERVOIRS. 


163 


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THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


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THE   CONTROL   OF  FLOODS   BY   RESERVOIRS. 


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180 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  15.     SAN  GABRIEL  RESER 

COMPARISON  OF  WATER  YIELD  FOR 

COORDINATED  WITH  SEASONAL 

Yearly  Summary  of  Computations 

(For  corresponding  monthly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Flood  control  by 

reservoir  operating  diagram 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant  draft  through  critical 

period 

;  constant  draft  of  22  sec.-ft.  maintained,  other  drafts  only  as  required  by 

reservoi 

r  operating  diagram 

Flood 

Ruu-o£E 

control 

Year 

at  Azusa 

water 

Constant 

draft 
from  over- 
year storage 
(22  second- 
feet)  in 
acre-feet 

in  acre-feet 

Stage  of 
reservoir 

at 
beginning 

of  year 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

passing 
Azusa 
during 

flood  season 
at  rates 
less  than 

1,900  second- 
feet  in 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface 

in  acre-feet 

Waste 

over 

spillway 

in  acre-feet 

acre-feet 

1897 

96,270 

62,650 

52,963 

16,407 

15.922 

16.901 

2,466 

0 

1898 

15,687 

54,261 

15,687 

0 

15,922 

0 

1,926 

0 

1899 

10,463 

36,413 

10,463 

0 

15,922 

0 

1,448 

0 

1900 

21,986 

19,043 

11,976 

0 

15,922 

0 

796 

0 

1901 

89,560 

12,335 

50,570 

0 

15,922 

0 

1,846 

0 

1902 

22,314 

33,557 

21,816 

0 

15,922 

0 

1,374 

0 

1903 

106,985 

16,759 

50,037 

0 

15.922 

4.235 

2,293 

0 

1904 

26  836 

51,257 

24,180 

0 

15,965 

0 

1,922 

0 

1905 

164,715 

36,026 

62,587 

13,658 

15.922 

54.628 

2,781 

0 

1906 

241,430 

51,265 

67,456 

39,397 

15.922 

107.768 

3,189 

0 

1907 

345,320 

58,963 

82,808 

127,639 

16,922 

123.335 

3,301 

0 

1908 

72,950 

51,278 

56,444 

10,159 

15.965 

0 

2,012 

0 

1909 

199,540 

39,648 

72,10) 

52,260 

15.922 

32.119 

2,593 

0 

1910 

118,450 

64,193 

54,518 

75,162 

15.922 

0 

1,892 

0 

1911 

276,280 

35,149 

70,413 

100,816 

15.922 

70,041 

2,916 

0 

1912 

73,620 

51,321 

47,362 

0 

15,965 

7.761 

2.356 

0 

1913 

50,323 

51,497 

40,386 

0 

15,922 

0 

2.099 

0 

1914 

299,710 

43,413 

72,456 

145,722 

16,922 

64,901 

2,786 

0 

1915 

131,800 

51,337 

73,157 

15,984 

15,922 

24.232 

2,514 

0 

1916 

294,220 

51,328 

77,852 

152,317 

15,966 

36.626 

2,625 

0 

1917 

72,710 

60,164 

60,160 

10,464 

16,922 

0 

2,122 

0 

1918 

137,140 

44,206 

58,741 

3,595 

15,922 

49.016 

2.741 

0 

1919 

38,005 

51,331 

37,874 

0 

16,922 

0 

1,848 

0 

1920 

113,730 

33,692 

60,683 

0 

15,965 

16,978 

2.454 

0 

1921 

186,760 

51.342 

54,013 

39,506 

15,922 

606 

2,269 

0 

1922 

316,690 

125,786 

87,587 

195.520 

16,922 

77.276 

2.970 

0 

1923 

51,750 

63,201 

51,298 

12,066 

16,922 

0 

1,868 

0 

1924 

25,933 

33,817 

25,517 

0 

15,965 

0 

1,380 

0 

1925 

23,400 

16,888 

21,878 

0 

16,922 

0 

744 

0 

•1926 

107,400 

1,744 

40,320 

0 

11.909 

0 

1,866 

0 

Total 

3,731,977 

1,513,303 

^1,010,662 

473,905 

676.322 

65,386 

0 

Average 

125,446 

50,867 

b33,972 

15,930 

22,734 

2.198 

»  Partial  year,  January  1  to  October  1. 

•>  These  figures  contain  7601  acre-feet  total  or  an  average  of  256  acre-feet  per  season  of  water  contributed  from  outside 
the  exact  period  of  analysis.  In  the  computations  from  which  this  table  is  prepared,  the  water  in  storage  on  October  1,  1926, 
the  end  of  the  period,  is  less  by  this  amount  than  on  January  1,  1897,  the  beginning  of  the  period.  Since  in  the  computations 
this  water  was  released  as  flood  control  water  during  the  first  flood  season  of  the  period,  the  exact  yield  of  flood  control  water 
for  the  period  is  less  than  hereshown  by  this  amount. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


181 


VOIR  ON  SAN  GABRIEL  RIVER. 
TWO  METHODS  OF  FLOOD  CONTROL 
AND  OVER- YEAR  STORAGE. 

Carried  out  on  a  Daily  Basis. 

mary,  see  Table  1 5a,  page  404.) 

Maximum  controlled  flow  at  Azusa  1900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 
Reservoir  emptied  of  seasonal  storage  each  year- 


Flood  control,  holding  maximum  reservoir  space  required  (131,000  ac.-ft.)  In  reserve 

throughout  flood  season 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  18  sec.-ft.  maintained,  other  drafts  only  as  required  by 

reservoir  operating  diagram 


Flood 

control 

water 

Constant 

Year 

Stage  of 
reservoir 

at 
beginning 

of  year 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

passing 
Azusa 
during 
flood  season 
at  rates 
less  than 
1,900  second- 
feet  in 
acre-feet 

draft 
from  over- 
year storage 
(18  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface 

in  acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

49,122 

52,963 

33,933 

13,032 

0 

2,006 

0 

-1897 

43,458 

15,687 

0 

13,032 

0 

1,688 

0 

1898 

28,738 

10,463 

0 

13,032 

0 

1,263 

0 

1899 

14,443 

11,976 

0 

13,032 

0 

644 

0 

1900 

10,777 

50,570 

0 

13,032 

0 

1,854 

0 

1901 

34,881 

21,816 

0 

13,032 

0 

1,463 

0 

1902 

20,884 

50,037 

11,429 

13,032 

4,588 

2,186 

0 

1903 

46,597 

24,180 

0 

13,068 

0 

1,836 

0 

1904 

34,349 

62,587 

73,010 

13,032 

1,734 

2,140 

0 

1905 

46,561 

67,456 

136,655 

13,032 

19,376 

2,350 

0 

1906 

49,122 

82,808 

228,430 

13,032 

21,229 

2,352 

0 

1907 

46,591 

56,444 

10,356 

13,068 

0 

1,928 

0 

1908 

37,745 

72,101 

91,415 

13,032 

2,644 

2,165 

0 

1909 

55,928 

54,518 

68.002 

13,032 

0 

1,911 

0 

1910 

36,915 

70,413 

176,382 

13,032 

4,617 

?,194 

0 

1911 

46,557 

47,362 

13,060 

13,068 

0 

2,082 

0 

1912 

44,605 

40,386 

2,687 

13,032 

0 

1,909 

0 

1913 

36,914 

72,456 

197,801 

13,032 

4,554 

2,176 

0 

1914 

46,605 

73,157 

35,855 

13,032 

7,618 

2,201 

0 

1915 

46,542 

77,852 

198,835 

13,068 

0 

2,028 

0 

1916 

48,979 

60,160 

8,027 

13,032 

0 

1,946 

0 

1917 

38,524 

58,741 

60,968 

13,032 

0 

2,000 

0 

1918 

40,923 

37,874 

0 

13,032 

0 

1,623 

0 

1919 

26,399 

60,683 

20,118 

13,068 

0 

2,068 

0 

1920 

44,192 

54,013 

46,315 

13,032 

352 

2,108 

0 

1921 

115,102 

87,587 

259,909 

13,032 

19,973 

2,328 

0 

1922 

48,963 

51,298 

0 

13,032 

0 

1,850 

0 

1923 

34,533 

25,517 

0 

13,068 

0 

1,453 

0 

1924 

20,428 

21.878 

0 

13.032 

0 

1,010 

0 

1925 

7.908 

40,320 

11,836 

9,747 

1,088 

1,772 

0 

"1926 

1,513.303 

1,685,053 

387,891 

^87,773 

56,534 

0 

Total 

50,867 

56,641 

13,039 

'■2,950 

1,900 

Average 

<:  In  the  computations  for  this  table,  the  period  of  analysis  closed  with  1423  acre-feet  more  water  in  storage  than  at  the 
beginning,  the  equivalent  of  48  acre-feet  per  season.  Since  in  the  computations  this  water  was  stored  in  the  last  year  of  the 
period  of  analysis,  the  exact  yield  in  seasonally  stored  water  for  the  period  is  larger  than  here  shown  by  this  amount. 


182 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  16.    SAN  GABRIEL  RESER 

COMPARISON  OF  WATER  YIELD  FOR 

THE  USE  OF 

Yearly  Summary  of  Computations 

(For  corresponding  monthly  sum 

Natural  flow  up  to  152  second- 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 


Flood  control  alone 

Flood  control  partially  coordinated 

Water  drawn  from 

reservoir  only  as  required  by 

Constant  draft  of  22  sec.-ft.  maintained. 

reservoir  operating  diagram 

required  by  reservoir 

Flood 

Flood 

Run-off 
at 

control 
water 

control 
water 

Constant 
draft 

Year 

Azuaa 

Stage  of 

Passed 

passing 
Azusa 
during 
flood 

Evapora- 

Stage of 

Passed 

passing 
Azusa 
daring 
flood 

from 

in 

reservoir 

by  dam 

tion 

Waste 

reservoir 

by  dam 

over- 

acre-feet 

at 

for 

from 

over 

at 

for 

year 

beginning 

prior 

reservoir 

spillway 

beginning 

prior 

storage 

of 
year  in 
acre-feet 

rights 

in 

acre-feet 

season 
at  rates 
less  than 

1,900 
second- 
feet  in 
acre-feet 

surface 

in 
acre-feet 

in 
acre-feet 

of 
year  in 
acre-feet 

rights 

in 

acre-feet 

season 
at  rat«3 
less  than 

1,900 
second- 
feet  in 
acre-feet 

(22 

second- 
feet) 
in 

acre-feet 

1897 

96,270 

62,650 

52,963 

30,209 

2,830 

0 

62.650 

52,963 

16  407 

15,922 

1898 

15,687 

72,918 

15,687 

13,484 

2,273 

0 

70,937 

15,687 

10,849 

15,922 

1899 

10,463 

57,161 

10,463 

0 

2,219 

0 

42,090 

10.463 

0 

15.922 

1900 

21.986 

54,942 

11,976 

0 

2,166 

0 

24,561 

11,976 

0 

15,922 

1901 

89,560 

62,786 

50.570 

36,470 

2,405 

0 

17,571 

50,570 

0 

15,922 

1902 

22,314 

62,901 

21,816 

0 

2,357 

0 

38,663 

21,816 

0 

15,922 

1903 

106,985 

01,042 

50,037 

18,087 

3,100 

0 

21,716 

50.037 

0 

15.922 

1904 

26,836 

96,803 

24,180 

0 

3,157 

0 

60.266 

24.180 

0 

15.965 

1905 

164,715 

96,302 

62,587 

99,337 

3,569 

0 

44.803 

62.587 

32,989 

15,922 

1906 

241,430 

95,524 

67,456 

201,800 

4,497 

0 

94.565 

67,456 

184.996 

15,922 

1907 

345,320 

03,201 

82,808 

212,060 

4,663 

7,426 

63.201 

82,808 

201.165 

15,922 

1908 

72,950 

101,564 

56,444 

62.322 

2,245 

0 

100,648 

66.444 

59,629 

15,965 

1909 

199,540 

53,503 

72,101 

104,979 

3,124 

0 

39.648 

72,101 

75,341 

15,922 

1910 

118,450 

72,839 

54,518 

85,557 

2,072 

0 

72.839 

54,518 

83.808 

16,922 

1911 

276,280 

49,142 

70,413 

153,559 

3,871 

0 

35.149 

70,413 

124,229 

15,922 

1912 

73,620 

97,579 

47.362 

11,255 

3.573 

0 

97,099 

47.362 

496 

16,965 

1913 

50,323 

109,009 

40.386 

47,834 

2.546 

0 

103,463 

40.386 

39.503 

15,922 

1914 

299,710 

68,566 

72,456 

227,682 

3,549 

0 

55,522 

72,456 

198.812 

15,922 

1916 

131,800 

64,589 

73,157 

31,417 

2,967 

0 

64,589 

73,157 

29.236 

15,922 

1916 

294,220 

88,848 

77.852 

238,753 

3,262 

0 

75.288 

77,852 

209.378 

15,965 

1917 

72,710 

63,201 

60,160 

14.791 

2.302 

0 

63.201 

60.160 

13.501 

15,922 

1918 

137,140 

58,658 

58,741 

61.007 

3,629 

0 

44.206 

58.741 

31.054 

15,922 

1919 

38,005 

72,521 

37,874 

7,081 

2,568 

0 

72.261 

37,874 

0 

15.922 

1920 

113,730 

63,003 

60,683 

41,059 

3,263 

0 

54,111 

60,683 

16,619 

15.965 

1921 

186,760 

71,728 

64,013 

02,355 

2,484 

0 

71,466 

54.013 

60,199 

15,922 

1922 

316,690 

139,636 

87,687 

301,585 

3,953 

0 

125,786 

87.587 

271.925 

15,922 

1923 

51,750 

63.201 

51,298 

13,408 

2,048 

0 

63,201 

51,298 

12.056 

15,922 

1924 

25,933 

48,197 

25,517 

0 

2,012 

0 

33,817 

25,517 

0 

15.965 

1925 

23,400 

46.601 

21,878 

0 

1,984 

0 

16.888 

21,878 

0 

16.922 

•1926 

107,400 

46,139 

40.320 

0 

2,842 

0 

1,744 

40,320 

0 

11.909 

Total 

3,731,977 

1,513,303 

''2,078,091 

87,430 

7,426 

1,513,303 

•1,672,152 

473.905 

Average 

125,445 

50,867 

^69,785 

2,939 

250 

50,867 

■^56,207 

15.930 

"Partial  year,  January  1  to  October  1. 

''In  the  computations  for  this  table,  the  i>eriod  of  analysis  closed  with  47,727  acre-feet  more  water  in  storage  than  at  the 
beginning,  the  equivalent  of  1604  acro-fcct  per  season.  Since  in  the  computations  this  water  was  stored  in  the  last  year  of 
the  period  of  analysis,  the  exact  yield  of  flood  control  water  for  the  period  is  greater  than  here  shown  by  this  amount. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


183 


VOIR  ON  SAN  GABRIEL  RIVER. 

THREE  STEPS  IN  COORDINATING 
RESERVOIR  SPACE. 

Carried  out  on  a  Daily  Basis. 

mary,  see  Table  16a,  page  426.) 

feet  passed  for  prior  rights. 


Maximum  controlled  flow  at  Azusa  1900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 


with  conservation 

other  drafts  only  as 
operating  diagram 

Fiood  controi  completely  coordinated  with  conservation 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant  draft  through 

critical  period;  constant  draft  of  22  sec.-ft.  maintained,  other  drafts  only 

as  required  by  reservoir  operating  diagram 

Evapora- 
tion from 
reservoir 
surface  in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
year  in 
acre-feet 

Passed 

by  dam 

for 

prior 

rights 

in 

acre-feet 

Flood 
control 
water 
passing 
Azusa 
during 

flood 

season 

at  rates 

less  than 

1,900 
second- 
feet  in 
acre-feet 

Constant 
draft 
from 
over- 
year 
storage 

(22 
second- 
feet) 
in 
acre-feet 

Variable 
summer 
draft 
from 
seasonal 
storage 

in 
acre-feot 

Evapora- 
tion from 
reservoir 
surface  in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Year 

2,691 
2,076 
1,607 
1.078 
1,976 
1,523 
2,476 
2,154 
3,455 
4,420 
4,627 
2,012 
2,985 
1,892 
3,766 
3,433 
2,393 
3,453 
2,786 
3,112 
2,122 
3,368 
2,359 
3,108 
2,306 
3,841 
1,858 
1,380 
744 
1,866 

0. 
0 
0 
0 
0 
0 
0 
0 
0 
0 
3,351 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

62,650 
54,261 
36,413 
19,043 
12,335 
33,557 
16,759 
51,257 
36,026 
51,265 
58,963 
51,278 
39,648 
64,193 
35,149 
51,321 
51,497 
43,413 
51,337 
51,328 
60,164 
44,206 
51.331 
33,692 
51,342 
125,786 
63.201 
33,817 
16,888 
1,744 

52,963 
15,687 
10,463 
11,976 
50,570 
21,816 
50,037 
24,180 
62,587 
67,456 
82,808 
56,444 
72,101 
54,518 
70,413 
47,.362 
40,386 
72,456 
73,157 
77,852 
60,160 
58,741 
37,874 
60,683 
54,013 
87,587 
51,298 
25,617 
21,878 
40,320 

16,407 
0 
0 
0 
0 
0 
0 
0 

13,658 

39,397 
127,639 

10,159 

52,260 

75,1P2 

100,816 

0 

0 

145,722 

15,984 
152,317 

10,464 

3,595 

0 

0 

39,506 
195,520 

12,056 
0 
0 
0 

15,922 
15,922 
15,922 
15,922 
15,922 
15,922 
15,922 
15,965 
15,922 
15,922 
15,922 
15,965 
15,922 
15,922 
15,922 
15,965 
15,922 
15,922 
15,922 
15,965 
15,922 
15,922 
15,922 
15,965 
15,922 
15,922 
15,922 
15,965 
15,922 
11,909 

16.901 
0 
0 
0 
0 
0 
4,235 
0 

54,528 

107,768 

123,335 

0 

32,119 
0 

70,041 

7,761 

0 

54,901 

24,232 

36,625 
0 

49,016 
0 

16,978 
606 

77,276 
0 
0 
0 
0 

2,466 
1,926 
1,448 

796 
1,846 
1,374 
2,293 
1,922 
2,781 
3,189 
3,301 
2,012 
2,593 
1,892 
2,916 
2,356 
2,099 
2,785 
2,514 
2,625 
2,122 
2,741 
1,848 
2,454 
2,269 
2,970 
1,858 
1,380 

744 
1,866 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

1897 
1898 
1899 
1900 
1901 
1902 
1903 
1904 
1905 
1906 
1907 
1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 
"1926 

76,867 
2,584 

3,351 
113 

1,513,303 
50,867 

=1,010,662 
'^33,972 

473,905 
15,930 

676,322 
22,734 

65,386 
2,198 

0 
0 

Total 
Average 

"  These  figures  contain  7601  acre-feet  total  or  an  average  of  256  acre-feet  per  season  of  water  contributed  from  outside 
the  exact  period  of  analysis.  In  the  computations  from  which  this  table  is  prepared,  the  water  in  storage  on  October  1,  1926, 
the  end  of  the  period,  is  less  by  this  amount  than  on  January  1,  1897,  the  beginning  of  the  period.  Since  in  the  computations 
this  water  was  released  as  flood  control  water  during  the  first  flood  season  of  the  period,  the  exact  yield  of  flood  control  water 
for  the  period  is  less  than  here  shown  by  this  amount. 


184 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  17.     SAN  GABRIEL  RESER 

COMPARISON  OF  WATER  YIELD  FOR 
OPERATING  FOR  FLOOD  CONTROL 

Yearly  Summary  of  Computations 

(For  corresponding  monthly  sum 

Natural  flow  up  to  152  second- 
Maximum  controlled  flow  at  Azusa  1900  second-feet. 


Height  of  dam  383  feet 

Capacity  of  reservoi 

180,000  ac.-ft. 

Constant  draft  of  22  sec.-ft.  maintained,  other  drafts  only  as 

Run-off 

required  by  reservoir 

operating  diagr 

UD 

at 

Flood  control 

Year 

Azusa 

Stage  of 
reservoir  at 
beginning 
of  year  in 
acre-feet 

water  passing 

Constant  draft 

in 

Passed  by 

Azusa  during 

from  over- 

Evaporation 

Waste  over 

spillway  in 

acre-feet 

acre-feet 

dam  for 

flood  season  at 

year  storage 

from  reservoir 

prior  rights 

rates  less  than 

(22  second- 

surface 

in  acre-feet 

1,900  second- 

feet)  in 

in  acre-feet 

feet  in 

acre-feet 

acre-feet 

1897 

96.270 

62.650 

52,963 

16,407 

15,922 

2,691 

U 

1898 

15,687 

70,937 

15,687 

10,849 

15,922 

2,076 

0 

1899 

10,463 

42,090 

10,463 

0 

15,922 

1,607 

U 

1900 

21,986 

24,561 

11,976 

0 

15,922 

1,078 

0 

1901 

89,560 

17,571 

50,570 

0 

15.922 

1,976 

0 

1902 

22,314 

38,663 

21,816 

0 

15,922 

1,523 

0 

1903 

106,985 

21,716 

50,037 

0 

15,922 

2,476 

0 

1904 

26,836 

60.266 

24,180 

0 

15.965 

2,154 

0 

190.5 

164,715 

44,803 

62,587 

32,989 

15,922 

3,455 

0 

1906 

241.430 

94,565 

67,456 

184,996 

15.922 

.4,420 

0 

1907 

345,320 

63,201 

82,808 

201,165 

15,922 

4,627 

3,351 

1908 

72,950 

100,648 

56.444 

59,529 

15,965 

2,012 

0 

1909 

199,540 

39,648 

72,101 

75,341 

15,922 

2,985 

0 

1910 

118,450 

72,839 

54,518 

83,808 

15,922 

1,892 

0 

1911 

276.280 

35.149 

70,413 

124,229 

15,922 

3,766 

0 

1912 

73.620 

97,099 

47,362 

496 

15,965 

3,433 

0 

1913 

50,323 

103,463 

40,386 

39,563 

15,922 

2,393 

0 

1914 

299,710 

55.522 

72,456 

198,812 

15,922 

3,453 

0 

1915 

131,800 

64.589 

73,157 

29,236 

15,922 

2,786 

0 

1916 

294,220 

75.288 

77,852 

209,378 

15,965 

3,112 

0 

1917 

72,710 

63,201 

60,160 

13,501 

15,922 

2,122 

U 

1918 

137,140 

44,206 

58,741 

31,054 

15.922 

3,368 

0 

1919 

38,005 

72,261 

37,874 

0 

l.i.922 

2,359 

0 

1920 

113,730 

54,111 

60,683 

16,619 

1.5,965 

3,108 

0 

1921 

186,760 

71,466 

54,013 

60,199 

]  5,922 

2,306 

0 

1922 

316,690 

125,786 

87,587 

271,925 

15.922 

3.841 

0 

1923 

51.750 

63,201 

51,298 

12,056 

15,922 

1,858 

0 

1924 

25,933 

33,817 

25,517 

0 

15.965 

1,380 

0 

1925 

23,400 

16,888 

21,878 

0 

15,922 

744 

0 

•1920 

10/ ,400 

1,744 

40,320 

0 

11,909 

1,866 

0 

Total 

3.731,977 

1,513,303 

bl,672,152 

473.905 

76.867 

3,351 

Average 

125,445 

50,867 

''56,207 

15,930 

2,581 

113 

»  Partial  year,  January  1  to  October  1. 

•>  These  figures  contain  7601  acre-feet  total  or  an  average  of  256  acre-feet  per  season  of  water  contributed  from  outside 
the  ejtact  period  of  analysis.  In  the  computations  from  which  this  table  is  prepared,  the  water  in  storage  on  October  1,  1926, 
the  end  of  the  period,  is  less  by  this  amount  than  on  January  1,  1897,  the  beginning  of  the  period.  Since  in  the  computations 
this  water  was  released  as  flood  control  water  during  the  first  flood  season  of  the  period,  the  exact  yield  of  flood  control  water 
for  the  period  is  less  than  here  shown  ty  this  amount. 


fHE   CONTROL   OP   FLOODS   BY   RESERVOIRS. 


185 


VOIR  ON  SAN  GABRIEL  RIVER. 

TWO  SIZES  OF  RESERVOIR 
AND  CONSTANT  DRAFT  ONLY. 

Carried  out  on  a  Daily  Basis. 

mary,  see  Table  17a,  page  448.) 

feet  passed  for  prior  rights. 


Maximum  .flood  control  reserve  131,000  acre-feet. 

Height  of  dam  425  feet 

Capacity  of  reservoir 

240,000  ac.-ft. 

Constant  draft  of  41  sec.-ft.  maintained,  other  drafts  only  as 

reqoired  by  reservoir  operating  diagram 

Flood  control 

Stage  of 
reservoir  at 
beginning 
of  year  in 
acre-feet 

Passed  by 

water  passing 
Azusa  during 

Constant  draft 

Evaporation 

U^TnQfp  fivpr 

Year 

dam  for 
prior  rights 

flood  season  at 
rates  less  than 

(41  second- 
feet)  in 

from  reservoir 
surface 

11  doLC  UVCl 

spillway  in 

in  acre-feet 

1,900  second- 
feet  in 

acre-feet 

in  acre-feet 

acre-feet 

122,650 

52,963 

15,089 

29,672 

3,802 

0 

1897 

117,394 

15,687 

0 

29,672 

3,170 

0 

1898 

84,552 

10,463 

0 

29,672 

2,461 

0 

1899 

52,419 

11,976 

0 

29,672 

1,677 

0 

1900 

31,080 

50,570 

0 

29,672 

2,116 

0 

1901 

38,282 

21,816 

0 

29,672 

1,269 

0 

1902 

7,839 

50,037 

0 

29,672 

1,959 

0 

1903 

33,156 

24,180 

0 

29,754 

1,168 

0 

1904 

4,890 

62,587 

0 

29,672 

2,931 

0 

1905 

74,415 

67,456 

90,216 

29,672 

5,300 

0 

1906 

123,201 

82.808 

190,451 

29,672 

5,733 

0 

1907 

159,857 

56,444 

57,178 

29,754 

3,216 

0 

1908 

86,215 

72,101 

47,055 

29,672 

4,088 

0 

1909 

132,839 

54,518 

82,307 

29,672 

3,114 

0 

1910 

81,678 

70,413 

96,025 

29,672 

4,819 

0 

1911 

157,029 

47,362 

0 

29,754 

4,471 

0 

1912 

149,062 

40,386 

24,723 

29,672 

3,529 

0 

1913 

101,075 

72,456 

169,521 

29,672 

4,543 

0 

1914 

124.593 

73,157 

27,425 

29,672 

3,903 

0 

1915 

122,236 

77,852 

181,433 

29,754 

4,216 

0 

1916 

123,201 

60,160 

12,270 

29,672 

3,308 

0 

1917 

90,501 

58,741 

2,982 

29,672 

4,212 

0 

1918 

132,034 

37,874 

0 

29,672 

3.481 

0 

1919 

99,012 

60,683 

0 

29,754 

3,860 

0 

1920 

118,445 

54,013 

35,443 

29,672 

3.457 

0 

1921 

182,620 

87,587 

253,954 

29,672 

4,896 

0 

9122 

123,201 

51,298 

10,928 

29,672 

3,084 

0 

1923 

79,969 

25.517 

0 

29,754 

2,376 

0 

1924 

48,255 

21,878 

0 

29.672 

1,601 

0 

1925 

18,504 

40.320 

0 

22,193 

2,054 

0 

»1926 

1,513,303 

1,297,000 

'883,173 

99,814 

0 

Total 

50,867 

=43,597 

"29,686 

3,355 

0 

Average 

°  These  figures  contain  61,313  acre-feet  total  or  an  average  of  2060  acre-feet  per  season  of  water  contributed  from  outside 
the  exact  period  of  analysis.  In  the  computations  from  which  this  table  is  prepared  the  water  in  storage  on  October  1,  1926, 
the  end  of  the  period,  is  less  by  this  amount  than  on  January  1,  1897,  the  beginning  of  the  period  A  supplementary  analysis, 
having  the  same  amount  of  water  in  storage  at  the  beginning  and  at  the  end  of  the  period,  was  made  to  obtain  the  exact  yield 
for  the  period.  This  gave  47,900  and  23,300  acre-feet  per  season,  respectively,  for  the  flood  control  wate  rand  uniformly  con- 
tinuous flow  instead  of  43,597  and  29,686  acre-feet,  respectively,  that  are  shown  herein. 


12—52411 


186 


WATER  RESOURCES   OF   CALIFORNIA. 


TABLE  18.     SAN  GABRIEL  RESERVOIR  ON  SAN  GABRIEL  RIVER. 

AVERAGE  SIZE  OF  FLOWS  OF  WATER 

YIELD  FOR  THREE  STEPS  IN  COORDINATING  THE  USE  OF 

RESERVOIR  SPACE 

Height  of  dam,  383  feet.    Maximum  controlled  flow  at  Azusa,  1,900  second-feet. 
Capacity  of  reservoir,  Maximum  flood  control 

180,000  acre-feet.  reserve,  131,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Size  of  total  flow  at  Azusa  in  second-feet 

0-250 

Year 

Flood  control  alone 

Water  drawn  from  reservoir  only 

as  required  by  reservoir 

operating  diagram 

Flood  control  partially  coordinated 
with  conservation 

Constant  draft  of  22  seoond-feet 

maintained,  other  drafts  only 

as  required  by  reservoir 

operating  diagram 

Flood  control  completely  coordinated 
with  conservation 

Reservoir  emptied  each  summer 
to  a  level  that  would  maintain 
a  constant  draft  of  22  second-feet 
through  critical  period;  constant 
draft  of  22  second-feet  maintained, 
other  drafts  only  as  required  by 
reservoir  operating  diagram 

Flood 
control 

water 
passing 
Azusa 
during 

flood 
season 
at  rates 
less  than 

1,900 
second- 
feet  in 
acre-feet 

Seasonally 

stored 

water 

released 

as  a 
variable 
summer 
flow  in 
acre-feet 

Constant 
flow  from 
over-year 
storage  in 
acre-feet 

Flood 
control 

water 
passing 

Azusa 
during 

flood 
season 
at  rates 
less  than 

1,900 
second- 
feet  in 
acre-feet 

Seasonally 

stored 

water 

released 

as  a 
variable 
summer 
flow  in 
acre-feet 

Constant 
flow  from 
over-year 
storage  in 
acre-feet 

Flood 
control 
water 
passing 
Azusa 
during 
flood 
season 
at  rates 

less  than 

1,900 
second- 
feet  in 

acre-feet 

Seasonally 

stored 

water 

released 

as  a 
variable 
summer 
flow  in 
acre-feet 

Constant 
flow  from 
over-year 
storage  in 
acre-feet 

1897 
1898 
1899 
1900 
1901 
1902 
1903 
1904 
1905 
1906 
1907 
1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 
•1926 

4,122 

191 

0 

0 

889 

0 

1,808 

0 

513 

591 

4,590 

62 

1,409 

445 

1,342 

161 

0 

477 

597 

14 

793 

209 

137 

2,341 

0 

307 

984 

0 

0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

1,966 

107 

0 

0 

0 

0 

0 

0 

401 

688 

2,251 

23 

88 

310 

261 

143 

12 

151 

324 

0 

0 

78 

0 

1,375 

0 

225 

610 

0 

0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

I) 

0 
0 
0 
0 
0 
0 
0 
0 
0 

15,049 
15,747 
15,922 
15,922 
15,922 
15,922 
15,922 
15,965 
15,137 
13,391 
10,950 
15,179 
14,003 
14,307 
14,046 
15,921 
15,311 
12,694 
15,182 
12,563 
15,398 
14,831 
15,922 
15,485 
15,092 
11,342 
15,224 
15,965 
15,922 
11,909 

1,966 
0 
u 
U 
0 
0 

u 

0 

0 

0 

1,103 

148 

0 

310 

79 

0 

0 

156 

199 

134 

558 

0 

0 

0 

16 

298 

610 

0 

0 

0 

16,901 
0 
0 
0 
0 
0 
4,235 
0 

20,865 
0 
0 
U 

21,613 

0 

0 

7,761 

0 

15,509 

19,211 

29,799 
0 

26,724 
0 

16,978 
606 
0 
0 
0 
0 
0 

15,049 
15,922 
15,922 
15,922 
15,922 
15,922 
15,922 
15,965 
10,469 

7,635 

5,280 
15,484 
12.127 
14,397 

6,413 
15,965 
15,922 

7,676 
13.960 
12,564 
15,006 
12,040 
15,922 
15,965 
15,398 

5,104 
l.'),224 
15,965 
15.922 
11,909 

Total 
Average 

21,982 
739 

0 
0 

0 
0 

9,013 
303 

0 
0 

442,145 
14,862 

5,577 
188 

180,202 
6,057 

402.893 
13.543 

•  Partial  year.  January  1  to  October  1. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


187 


TABLE  18  (Continued).     SAN  GABRIEL  RESERVOIR  ON 
SAN  GABRIEL  RIVER. 

AVERAGE  SIZE  OF  FLOWS  OF  WATER 

YIELD  FOR  THREE  STEPS  IN  COORDINATING  THE  USE  OF 

RESERVOIR  SPACE 

Height  of  dam,  383  feet.    Maximum  controlled  flow  at  Azusa,  1,900  second-feet. 
Capacity  of  reservoir,  Maximum  flood  control 

180,000  acre-feet.  reserve,  131,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Size  of  total  flow  at  Azusa  in  second-feet 

250-500 

Flood  control  completely  coordinated 

Flood  control  alone 

Water  drawn  from  reservoir  only 

Flood  control  partially  coordinated 
with  conservation 

Constant  draft  of  22  second-feet 

with  conservation 

Reservoir  emptied  each  summer 
to  a  level  that  would  maintain 
a  constant  draft  of  22  second-feet 

as  required  by  reservoir 

maintained,  other  drafts  only 

through  critical  period;  constant 
draft  of  22  second-feet  maintained , 

operating  diagram 

as  required  by  reservoir 

operating  diagram 

other  drafts  only  as  required  by 
reservoir  operating  diagram 

Year 

Flood 

Flood 

Flood 

control 

control 

control 

water 

Seasonally 

water 

Seasonally 

water 

Seasonally 

passing 
Azusa 
during 
flood 

stored 
water 

Constant 

passing 
Azusa 
during 
flood 

stored 
water 

Constant 

passing 
Azusa 
during 
flood 

stored 
water 

Constant 

released 

flow  from 

released 

flow  from 

released 

flow  from 

as  a 

over-year 

as  a 

over-year 

as  a 

over-year 

season 
at  rates 
less  than 

1,900 
second- 

variable 
summer 
flow  in 
acre-feet 

storage  in 
acre-feet 

season 
at  rates 
less  than 

1,900 
second- 

variable 
summer 
flow  in 
acre-feet 

storage  in 
acre-feet 

season 
at  rates 
less  than 

1,900 
second- 

variable 
summer 
flow  in 
acre-feet 

storage  in 
acre-feet 

feet  in 

feet  in 

feet  in 

acre-feet 

acre-feet 

acre-feet 

1897 

12,490 

0 

0 

10.201 

0 

785 

10,201 

0 

785 

1898 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1899 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1900 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1901 

8,976 

0 

0 

0 

0 

0 

0 

0 

0 

1902 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1903 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1904 

0 

U 

0 

0 

0 

0 

0 

0 

0 

1905 

952 

0 

0 

1,699 

U 

174 

0 

33,564 

5,235 

1906 

2,815 

U 

0 

2,679 

0 

174 

0 

91,153 

0,804 

1907 

10,817 

(1 

0 

7,^72 

0 

1,090 

2,696 

49,281 

4,100 

1908 

0 

0 

0 

566 

0 

44 

1,286 

0 

262 

t_       1909 

2,624 

0 

0 

4,553 

0 

524 

4,553 

10,506 

3,011 

t      1910 

3,861 

0 

0 

3,468 

0 

393 

3,468 

0 

393 

f       1911 

1,156 

0 

0 

634 

0 

87 

634 

70,041 

8,070 

1912 

0 

0 

0 

353 

0 

44 

0 

0 

0 

1913 

0 

0 

0 

1.191 

0 

131 

0 

0 

0 

1914 

4,524 

0 

0 

5,633 

0 

480 

1,994 

39,392 

6,195 

1915 

2,581 

0 

0 

2,186 

0 

218 

2,170 

5,021 

1,570 

1916 

3,074 

0 

0 

2,304 

0 

174 

468 

6,825 

1,484 

1917 

8,843 

0 

0 

8,589 

0 

262 

7,658 

0 

785 

1918 

2,197 

0 

0 

2,149 

0 

175 

0 

22,293 

3.795 

1919 

1,686 

0 

0 

0 

0 

0 

0 

0 

0 

1920 

11,700 

0 

0 

3,424 

0 

218 

0 

0 

0 

1921 

0 

0 

0 

352 

0 

44 

0 

0 

0 

1922 

2,899 

0 

0 

2,714 

0 

218 

955 

77,275 

8,071 

1923 

4,220 

0 

0 

3,871 

0 

349 

3,871 

0 

349 

1924 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1925 

0 

0 

0 

0 

0 

0 

0 

0 

0 

M926 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Total 

85,315 

0 

0 

64,338 

0 

5,584 

39,954 

405,451 

50,909 

Average 

2,868  1                0 

0 

2,162 

0 

188 

1,343 

13,629 

1,711 

'  Partial  year.  January  1  to  October  1. 


188 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  18  (Continued).     SAN  GABRIEL  RESERVOIR  ON 
SAN  GABRIEL  RIVER. 

AVERAGE  SIZE  OF  FLOWS  OF  WATER 

YIELD  FOR  THREE  STEPS  IN  COORDINATING  THE  USE  OF 

RESERVOIR  SPACE 


Height  of  dam,  383  feet.   Maximum  controlled  flow  at  Azusa,  1,900  second-feet. 
Capacity  of  reservoir,  Maximum  flood  control 

180,000  acre-feet.  reserve,  131,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Size  of  total  flow  at  Azusa  in  second-feet 

500-750 

Year 

Flood  control  alone 

Water  drawn  from  reservoir  only 

as  required  by  reservoir 

operating  diagram 

Flood  control  partially  coordinated 
with  conservation 

Constant  draft  of  22  second-feet 

maintained,  other  drafts  only 

as  required  by  reservoir 

operating  diagram 

Flood  control  completely  coordinated 
with  conservation 

Reser\-oir  emptied  each  summer 
to  a  level  that  would  maintain 
a  constant  draft  of  22  second-feet 
through  critical  period;  constant 
draft  of  22  second-feet  maintained, 
other  drafts  only  as  required  by 
reservoir  operating  diagram 

Flood 
control 

water 
passing 
Azusa 
during 

flood 
season 
at  rates 
less  than 

1,900 
second- 
feet  in 
acre-feet 

Seasonally 

stored 

water 

released 

as  a 
variable 
summer 
flow  in 
acre-feet 

Constant 
flow  from 
over-year 
storage  in 

acre-feet 

Flood 
control 
water 
passing 
Azusa 
during 

flood 

season 

at  rates 

less  than 

1,900 
second- 
feet  in 
acre-feet 

Seasonally 

stored 

water 

released 

as  a 
variable 
summer 
flow  in 
acre-feet 

Constant 
flow  from 
over-year 
storage  in 
acre-feet 

Flood 
control 
water 
passing 
Azusa 
during 

flood 
season 
at  rates 
less  than 

1,900 
second- 
feet  in 
acre-feet 

Seasonally 

stored 

water 

released 

as  a 
variable 
summer 
flow  in 
acre-feet 

Constant 
flow  from 
over-year 
storage  in 
acre-feet 

1897 
1898 
1899 
1900 
1901 
1902 
1903 
1904 
1905 
1906 
1907 
1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 
•1926 

3.366 

0 

0 

0 

11,032 

0 

0 

0 

2,133 

3,195 

14,447 

0 

3,735 

2,833 

5,594 

0 

823 

4.809 

1,816 

15,131 

5,155 

13,094 

5,358 

8,181 

878 

5,753 

6,225 

0 

0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

990 

1,316 

0 

0 

0 

0 

0 

0 

1,345 

3,177 

13,749 

0 

0,253 

2,705 

5.907 

0 

0 

5,780 

2,200 

14,527 

4,912 

11,619 

0 

3,402 

0 

8,547 

5,683 

0 

0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

44 

44 

0 

0 

0 

0 

U 

0 

44 

131 

654 

0 

305 

131 

305 

0 

0 

262 

87 

611 

262 

480 

0 

131 

0 

392 

305 

0 

0 

0 

990 

0 

0 

0 

0 

0 

0 

0 

0 

0 

8,960 

1,064 

2.988 

2,705 

4,161 

0 

0 

3,673 

1,682 

0 

2,248 

0 

0 

0 

1,107 

5,696 

5,683 

0 

0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
14.756 
74.054 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

44 

0 

0 

0 

0 

(1 

0 

U 

0 

960 

4,624 

44 

175 

131 

218 

0 

0 

174 

87 

0 

131 

0 

0 

0 

44 

262 

305 

0 

0 

0 

Total 
Average 

113.618 
3.810 

0 
0 

0 
0 

92,112 
3,096 

0 
0 

4,188 
Ul 

40,957 
1.377 

88.810 
2,985 

7,199 
242 

•  Partial  year,  January  1  to  October  1. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


189 


TABLE  18  (Continued).     SAN  GABRIEL  RESERVOIR  ON 
SAN  GABRIEL  RIVER. 

AVERAGE  SIZE  OF  FLOWS  OF  WATER 

YIELD  FOR  THREE  STEPS  IN  COORDINATING  THE  USE  OF 

RESERVOIR  SPACE 

Height  of  dam,  383  feet.    Maximum  controlled  flow  at  Azusa,  1,900  second-feet. 
Capacity  of  reservoir,  Maximum  flood  control 

180,000  acre-feet.  reserve,  131,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Size  of  total  flew  at  Azusa 

in  second-feet 

750-1,000 

Flood  control  completely  coordinated 

Flood  control  alone 

Water  drawn  from  reservoir  only 

Flood  control  partially  coordinated 
with  conservation 

Constant  draft  of  22  second-feet 

with  conservation 

Reservoir  emptied  each  summer 
to  a  level  that  would  maintain 
a  constant  draft  of  22  second-feet 

as  required  by  reservoir 

maintained,  other  drafts  only 

through  critical  period;  constant 

operating  diagram 

as  required  byreservoir 

draft  of  22  second-feet  maintained, 

operating  diagram 

other  drafts  only  as  required  by 

reservoir  operating  diagram 

Year 

Flood 

Flood 

Flood 

control 

control 

control 

water 

Seasonally 

water 

Seasonally 

water 

Seasonally 

passing 
Aziisa 

stored 
water 

Constant 

passing 
Azusa 
during 
flood 

stored 
water 

Constant 

passing 
Azusa 
during 
flood 

stored 
water 

Constant 

during 
flood 

released 

flow  from 

released 

flow  from 

released 

flow  from 

as  a 

over-year 

as  a 

over-year 

as  a 

over-year 

season 
at  rates 
less  than 

1,900 
second- 

variable 
Slimmer 
flow  in 
acre-feet 

storage  in 
acre-feet 

season 
at  rates 
less  than 

1,900 
second- 

variable 
Slimmer 
flow  in 
acre-feet 

storage  in 
acre-feet 

season 
at  rates 
less  than 

1,900 
second- 

variable 
summer 
flow  in 
acre-feet 

storage  in 
acre-feet 

feet  in 

feet  in 

feet  in 

acre-feet 

acre-feet 

acre-feet 

1897 

1,783 

0 

0 

0 

0 

0 

0 

0 

0 

1898 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1899 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1900 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1901 

5,590 

0 

0 

0 

c 

0 

0 

0 

0 

1902 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1903 

0 

0 

0 

0 

0 

c 

0 

0 

0 

1904 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1905 

3,360 

0 

0 

10  971 

3 

305 

1,520 

0 

44 

1906 

3,183 

0 

0 

4,145 

0 

131 

0 

0 

0 

1907 

17,511 

0 

0 

ices'? 

0 

524 

13,220 

0 

393 

1908 

0 

0 

0 

0 

0 

0 

2,800 

0 

87 

1909 

11,714 

0 

0 

10,091 

0 

305 

1,427 

0 

44 

1910 

4,034 

0 

0 

3,903 

0 

131 

5,393 

0 

174 

1911 

1,563 

0 

0 

0 

0 

0 

0 

0 

0 

1912 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1913 

1,501 

0 

0 

0 

0 

0 

0 

0 

0 

1914 

0 

0 

0 

2,504 

0 

87 

3,740 

0 

131 

1915 

0,824 

0 

0 

c,204 

0 

174 

5,204 

0 

174 

1916 

16,279 

0 

0 

9,467 

0 

305 

0 

0 

0 

1917 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1918 

16,235 

0 

0 

7,715 

0 

218 

0 

0 

0 

1919 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1920 

9,715 

0 

0 

1,546 

0 

14 

0 

0 

0 

1921 

1,436 

0 

0 

1,215 

0 

44 

0 

0 

0 

1922 

24,377 

0 

0 

24,627 

0 

742 

3.919 

0 

131 

1923 

0 

0 

0 

0 

0 

0 

0 

■    0 

0 

1924 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1925 

0 

0 

0 

0 

0 

0 

0 

0 

0 

"1926 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Total 

125,105 

0 

0 

98,221 

0 

3,010 

37,223 

0 

1.178 

Average 

4,205 

0 

0 

3,302 

(» 

101 

1,251 

0 

40 

•  Partial  year,  January  1  to  October  1. 


190 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  18  (Continued).     SAN  GABRIEL  RESERVOIR  ON 
SAN  GABRIEL  RIVER. 

AVERAGE  SIZE  OF  FLOWS  OF  WATER 

YIELD  FOR  THREE  STEPS  IN  COORDINATING  THE  USE  OF 

RESERVOIR  SPACE. 


Height  of  dam,  383  feet.    Maximum  controlled  flow  at  Azusa,  1,900  second-feet. 
Capacity  of  reservoir.  Maximum  flood  control 

180,000  acre-feet.  reserve,  131,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Size  of  total  flow  at  Azusa  in  second-feet 

1.000-1,250 

1 

Flood  control  completely  coordinated 

Flood  control  alone 

Water  drawn  from  reservoir  only 

as  required  by  reservoir 

operating  diagram 

Flood  control  partially  coordinated 
with  conservation 

Constant  draft  of  22  second-feet 

maintained,  other  drafts  only 

as  required  by  reservoir 

operating  diagram 

with  conservation 

Reservoir  emptied  each  summer 
to  a  level  that  would  maintain 
a  constant  draft  of  22  second-feet 
through  critical  period;  constant 
draft  of  22  second-feet  maintained, 
other  drafts  only  as  required  by 

reservoir  operating  diagram 

Year 

Flood 

Flood 

Flood 

control 

control 

control 

water 

Seasonally 

water 

Seasonally 

water 

Seasonally 

passing 
Aiusa 

during 
flood 

stored 
water 

Constant 

passing 
Azusa 
during 
flood 

stored 
water 

Constant 

passing 
Azusa 
during 
flood 

stored 
water 

Constant 

released 

flow  from 

released 

flow  from 

released 

flow  from 

as  a 

over-year 

as  a 

over-year 

as  a 

over-year 

season 
at  rates 
less  than 

1,900 
second- 

variable 

storage  in 

season 
at  rates 
less  than 

1,900 
second- 

variable 

storage  in 

season 
at  rates 
less  than 

1,900 
secopd- 

variable 

storage  in 

summer 
flow  in 
acre-feet 

acre-feet 

summer 
flow  in 
acre-feet 

acre-feet 

summer 
flow  in 
acre-feet 

acre-feet 

feet  in 

feet  in 

feetin 

acre-feet 

acre-feet 

acre-feet 

1897 

2,181 

0 

0 

0 

0 

0 

0 

0 

0 

1898 

2,199 

0 

0 

2,136 

0 

44 

0 

0 

0 

1899 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1900 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1901 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1902 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1903 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1904 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1905 

8,014 

0 

0 

1.923 

0 

44 

1.850 

0 

44 

1906 

2,182 

0 

0 

2,238 

0 

44 

0 

0 

0 

1907 

42,477 

0 

0 

41,522 

0 

916 

25,319 

0 

523 

1908 

0 

0 

0 

0 

0 

0 

2,136 

0 

44 

1909 

9,501 

0 

0 

9,302 

0 

218 

1.679 

0 

44 

1910 

1,802 

0 

0 

1,758 

0 

44 

1,741 

0 

44 

1911 

6,102 

0 

0 

2,013 

0 

44 

2,013 

0 

44 

1912 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1913 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1914 

0 

0 

0 

5,845 

0 

131 

1,909 

0 

44 

1915 

2.059 

0 

0 

2,014 

0 

43 

3,959 

0 

87 

1916 

6,170 

0 

0 

4,061 

0 

87 

0 

0 

0 

1917 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1918 

11,795 

0 

0 

9,493 

0 

218 

3,594 

0 

87 

1919 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1920 

2,182 

0 

0 

0 

0 

0 

0 

0 

0 

1921 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1922 

20,396 

u 

0 

17.755 

0 

392 

0 

0 

0 

1923 

1,979 

0 

0 

1,892 

0 

44 

1.892 

0 

44 

1924 

0 

u 

0 

0 

0 

0 

0 

u 

0 

1925 

U 

0 

0 

0 

0 

0 

0 

0 

u 

•1926 

0 

0 

0 

0 

0 

u 

U 

0 

u 

ToUl 

119.039 

0 

0 

101.952 

0 

2,269 

46,092 

0 

1.005 

Average 

4,001 

0 

0 

3,427 

0 

76 

1,549 

0 

34 

■  Partial  year,  January  1  to  October  1. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


191 


TABLE  18  (Continued).     SAN  GABRIEL  RESERVOIR  ON 
SAN  GABRIEL  RIVER. 

AVERAGE  SIZE  OF  FLOWS  OF  WATER 

YIELD  FOR  THREE  STEPS  IN  COORDINATING  THE  USE  OF 

RESERVOIR  SPACE. 

Height  of  dam,  383  feet.   Maximum  controlled  flow  at  Azusa,  1,900  second-feet. 
Capacity  of  reservoir.  Maximum  flood  control 

180,000  acre-feet.  reserve,  131,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Size  of  total  flow  at  Azusa  In  second-feet 

1,250-1,500 

Year 

Flood  control  alone 

Water  drawn  from  reservoir  only 

as  required  by  reservoir 

operating  diagram 

Flood  control  partially  coordinated 
with  conservation 

Constant  draft  of  22  second-feet 

maintained,  other  drafts  only 

as  req  Jired  by  reservoir 

operating  diagram 

Flood  control  completely  coordinated 
with  conservation 

Reservoir  emptied  each  summer 
to  a  level  that  would  maintain 
a  constant  draft  of  22  second-feet 
through  critical  period;  constant 
draft  of  22  second-feet  maintained, 
other  drafts  only  as  required  by 
reservoir  operating  diagram 

Flood 
control 

water 
passing 

Azusa 
during 

flood 
season 
at  rates 
less  than 

1,900 
second- 
feet  in 
acre-feet 

Seasonally 

stored 

water 

released 

as  a 
variable 
summer 
flow  in 
acre-feet 

Constant 
flow  from 
over-year 
storage  in 
acre-feet 

Flood 
control 

water 
passing 

Azusa 
during 

flood 

season 

at  rates 

less  than 

1,900 
second- 
feet  in 
acre-feet 

Seasonally 

stored 

water 

released 

as  a 
variable 
summer 
flow  in 
acre-feet 

Constant 
flow  from 
over-year 
storage  in 

acre-feet 

Flood 
control 

water 
passing 

Azusa 
during 

flood 
season 
at  rates 
less  than 

1,900 
second- 
feet  in 
acre-feet 

Seasonally 

stored 

water 

released 

as  a 
variable 
summer 
flow  in 
acre-feet 

Constant 
flow  from 
over-year 
storage  in 
acre-feet 

1897 
1898 
1899 
1900 
1901 
1902 
1903 
1904 
1905 
1906 
1907 
1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 
n926 

0 
0 
0 
0 
0 
0 

2,255 

0 

0 

0 

46,603 

2,576 

2,404 

2,435 
0 
0 
0 

2,284 
0 

8,806 
0 
0 
0 
0 
0 

14,287 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

(J 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 

2,957 

43,615 

0 

0 

2,391 
0 
0 
0 

4,890 
0 

2,334 
0 
0 
0 
0 
0 
11,906 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 

44 

785 

0 

0 

44 
0 
0 
0 

87 
0 

44 
0 
0 
0 
0 
0 
218 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
12,354 
0 
0 
0 
0 
0 
0 

2,157 
0 
0 
0 
0 
0 
0 
0 

4,861 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
218 
0 
0 
0 
0 
0 
0 

44 
0 
0 
0 
0 
0 
0 
0 

87 
0 
0 
0 
0 

Total 
Average 

81.650 
2,745 

0 
0 

0 
0 

68,093 
2,289 

0 
0 

1,222 
41 

19,372 
651 

0 
0 

349 
12 

•  Partial  year,  January  1  to  October  1. 


192 


WATER   RESOURCES   OP    CALIFORNIA. 


TABLE  18  (Continued).     SAN  GABRIEL  RESERVOIR  ON 
SAN  GABRIEL  RIVER. 

AVERAGE  SIZE  OF  FLOWS  OF  WATER 

YIELD  FOR  THREE  STEPS  IN  COORDINATING  THE  USE  OF 

RESERVOIR  SPACE. 


Height  of  dam,  383  feet.    Maximum  controlled  flow  at  Azusa,  1,900  second-feet. 

Capacity  of  reservoir,  Maximum  flood  control 

180,000  acre-feet.  reserve,  131,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Size  of  total  flow  at  Azusa 

in  second-feet 

1,500-1,900 

Year 

Flood  control  alone 

Water  drawn  from  reservoir  only 

as  required  by  reservoir 

operating  diagram 

Flood  control  partially  coordinated 
with  conservation 

Constant  draft  of  22  second-feet 

maintained,  other  drafts  only 

as  required  by  reservoir 

operating  diagram 

Flood  control  completely  coordi  nated 

with  conservation 
Reservoir  emptied  each  summer 
to  a  level  that    would  maintain 
a  constant  draft  of  22  second-feet 
through  critical  period;  constant 
draft  of  22  second-feet  maintained, 
other  drafts  only  as  required  by 
reservoir  operating  diagram 

Flood 
control 

water 
passing 
Azusa 
during 

flood 
season 
at  rates 
less  than 

1.900 
second- 
feet  in 
acre-feet 

Seasonally 

stored 

water 

released 

as  a 
variable 
summer 
flow  in 
acre  feet 

Constant 
flow  from 
over  year 
storage  in 
!\cre  feet 

Flood 
control 
water 
passing 
Azusa 
during 

flood 

season 

at  rates 

less  than 

1,900 
second- 
feet  in 
acre-feet 

Seasonally 

stored 

water 

released 

as  a 
variable 
summer 
flow  in 
acre  feet 

Constant 
flow  from 
overyear 
storage  in 
acre-feet 

Flood 
control 

water 
passing 

Azusa 
during 

flood 
season 
at  rates 
less  than 

1,900 
second- 
feet  in 
acre-feet 

Seasonally 

stored 

water 

1  eleased 

as  a 
i'ariable 
summer 
flow  in 
acre  feet 

Constant 
flow  from 
over  year 
storage  in 
acre-feet 

1897 
1898 
1899 
1900 
1901 
1902 
1903 
1904 
1905 
1906 
1907 
1908 
1909 
1910 
1911 
1912 
1913 
1914 
1915 
1916 
1917 
1918 
1919 
1920 
1921 
1922 
1923 
1924 
1925 
•1926 

6.267 

11.094 

0 

0 

9.983 

0 

14.024 

0 

84.365 

189,834 

83.041 

59,684 

73,592 

70,147 

137,802 

11,094 

45,510 

215,528 

17,540 

189,279 

0 

17.477 

0 

6.940 

60.041 

233,566 

0 

0 

0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

u 

0 
0 

3,250 

7,290 

0 

0 

0 

0 

0 

0 

16.650 

169.112 

78.774 

58.940 

45.054 

69.273 

115.414 

0 

38.360 

174,009 

17,308 

1/6,686 

0 

0 

0 

6,872 

58,632 

206,151 

0 

0 

U 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

u 

0 
0 
0 
0 
0 

44 

87 

0 

0 

0 

0 

0 

0 

218 

2,007 

1,003 

742 

567 

872 

1,440 

0 

480 

2,181 

218 

2,181 

0 

0 

0 

87 

742 

2,618 

0 

0 

0 

0 

3,250 

0 

0 

0 

0 

0 

0 

0 

10,287 

23,964 

63,987 

2,725 

41,613 

61,545 

93,929 

0 

0 

132,093 

2,770 

151,716 

0 

0 

0 

0 

38,383 

179,792 

0 

0 

0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
l/,292 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

u 

0 

44 

0 

0 

0 

0 

0 

0 

0 

130 

523 

784 

44 

521 

783 

1,177 

0 

0 

1,658 

44 

1,917 

0 

0 

0 

0 

480 

2,267 

0 

0 

0 

0 

Total 
Average 

1.536,808 
51,658 

0 
0 

0 
0 

1.241,774 
41,741 

0 
0 

15,487 
521 

806,054 
27,095 

17,292 
581 

10,372 
348 

•  Partial  year,  January  1  to  October  1. 


I 


194 


WATER  RESOURCES  OF   CALIFORNIA. 


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198  WATER  RESOURCES  OF   CALIFORNIA. 

Performance  of  the  four  illustrative  reservoir  operating  diagrams  in  controlling 
floods  when  coordinated  with  conservation. 

The  last  section  of  Chapter  V  describes  the  performance  of  the  four 
illustrative  reservoir  operating  diagrams  in  controlling  floods.  Tests 
are  tabulated  of  their  application  to  the  records  of  all  important  floods 
on  their  respective  streams.  It  was  shown  that  reservoir  operation  in 
accord  with  these  diagrams  would  provide  more  space  than  needed  to 
detain  the  excess  water  of  all  floods  of  record  and  that  the  average 
space  to  spare  while  controlling  all  the  large  floods  of  record  would 
have  been  about  half  the  maximum  reserve.  In  these  computations, 
it  was  assumed  that  no  water  was  released  from  the  reservoir  except 
as  required  by  the  diagrams.  It  may  be  observed  in  reviewing  Plates 
XXIII  to  XXVI,  inclusive,  on  which  is  delineated  the  reservoir  stage 
while  so  controlling  floods,  together  with  the  stage  while  controlling 
floods  coordinately  Avith  conservation  as  described  in  this  chapter,  that  at 
times  the  reservoir  is  needlessly  full  of  water  when  operating  for  flood 
control  alone,  but  when  flood  control  is  coordinated  with  conservation, 
it  may  be  observed  that  the  draft  for  useful  purposes  lowers  the  reser- 
voir level  much  of  the  time  below  that  required  for  flood  control  only. 
At  these  times  the  space  available  for  detaining  flood  water  is  increased 
over  that  resulting  from  the  application  of  the  diagram  not  coordinated 
with  conservation.  Although  this  extra  empty  space  is  variable  in  the 
time  and  amount  of  its  occurrence,  nevertheless,  it  is  useful  in  detain- 
ing some  flood  water. 

Tables  of  unused  reservoir  space  in  controlling  the  floods  of  record 
when  flood  control  and  conservation  are  coordinated  as  described  in  this 
chapter,  are  prepared  in  parallel  to  those  of  Chapter  V  which  tabulates 
the  unused  space  in  controlling  the  same  floods  by  the  same  reservoirs 
and  by  the  same  reservoir  operating  diagrams  but  independently  of 
conservation.  A  comparison  of  these  tables  sliows  that  coordination 
with  conservation  as  herein  described  for  the  Kennett  reservoir  on  the 
Sacramento  River  did  not  alter  tlie  minimum  space  to  spare  of  53,500 
acre-feet  on  March  20,  1907,  but  did  increase  the  average  space  to 
spare  in  controlling  all  the  floods  of  record  from  52  to  85  per  cent  of 
the  maximum  flood  control  reserve.  Coordination  with  conservation 
in  the  Pardee  reservoir  on  the  Mokelumnc  River,  as  described  herein, 
increased  the  minimum  space  to  spare  in  controlling  the  rain-water 
floods  from  zero  to  6600  acre-feet  and  the  average  from  42  to  68  per 
cent  of  the  maximum  flood  control  reserve.  It  had  no  effect,  however, 
on  the  unused  space  in  controlling  snow-water  floods.  On  the  San 
Joaquin  River,  the  coordination  of  flood  control  and  conservation  in 
the  Temperance  Flat  reservoir,  as  described  herein,  increased  the 
minimum  unused  space  in  controlling  the  rain-water  floods  from  zero 
to  74,500  acre-feet  and  the  average  fi-om  37  to  370  per  cent  of  the 
maximum  flood  control  reserve.  It  did  not  increase  the  minimum 
unused  space  in  controlling  the  snow-water  floods  of  record  but  did 
raise  the  average  unused  space  from  53  to  111  per  cent  of  the  maximum 
space  required.  On  the  San  Gabriel  River,  coordination  of  flood  control 
with  seasonal  storage  and  a  constant  draft,  as  described  herein,  increased 
the  minimum  unused  space  from  12,700  to  32,600  acre-feet  and  the 
average  unused  space  while  regulating  all  the  floods  of  record  from  54 
to  69  per  cent  of  the  maximum  flood  control  reserve. 


THE   CONTROL   OP   FLOODS   BY  RESERVOIRS. 


199 


KENNETT  RESERVOIR  ON  SACRAMENTO  RIVER. 
UNUSED  SPACE  WHILE  CONTROLLING  ALL  FLOODS  OF  RECORD  BY 

RESERVOIR  OPERATING  DIAGRAM,  1895-1926. 
Reservoir  Operated  Coordinately  for  Irrigation  with  Incidental  Power,  and 

Flood  Control. 
Height  of  dam  420  feet.  Capacity  of  reservoir  2,940,000  acre-feet. 


Maximum  flood  flow- 

uncontrolled 

Flow  controlled  to  125,000  second-feet  maximum  near  Red  Bluff 

Reservoir  space  not  used  in 

Mean  daily  flow 
near  Red  Bluff 
in  second-feet 

Date  reservoir  nearest  full 

controlling  flood 

Date 

In  acre-feet 

In  per  cent  of 

maximum  space 

required  for 

flood  control 

(454,000  acre- 

feet) 

Feb.    3,  1909 

254,000 

Feb.    4,1909 

188,800 

42 

Feb.    2,1915 

249,000 

Feb.    2,  1915 

200,900 

44 

Mar.  20, 1907 

190,000 

Mar.  21, 1907 

53,500 

12 

Jan.  16, 1909 

188,000 

Jan.  18,  1909 

191,400 

42 

Feb.  16,  1904 

188,000 

Feb.  16. 1904 

357,700 

79 

Jan.  21,  1909 

177,000 

Jan.  21,  1909 

150,700 

33 

Feb.  25,  1917 

176,000 

Feb.  25,  1917 

761,400 

168 

Feb.  21,  1914 

160,000 

Feb.  21,  1914 

119,600 

26 

Jan.     1,  1914 

151,000 

Jan.     2, 1914 

926,300 

204 

Feb.  24, 1902 

151,000 

Feb.  26,  1902 

289,100 

64 

Mar.   8,  1904 

147,000 

Mat.  8, 1904 

332,400 

73 

Feb.  10,  1902 

140,000 

Feb.  12, 1902 

528,400 

116 

Mar.  31,  1906 

137,000 

Mar.  31, 1906 

105,500 

23 

Jan.  19, 1906 

136,000 

Jan.   19,  1906 

1,158,800 

255 

Feb.    4,  1907 

134,000 

Feb.    4,  1907 

433,500 

95 

Jan.  25,1903 

131,000 

Jan.  25,1903 

431,700 

95 

Mar.   7,  1911 

130,000 

Mar.  7,  1911 

368,400 

81 

Jan.  27,1896 

128,000 

Jan.  27,  1896 

341,500 

75 

Average 

385,500 

85 

\ 


200 


WATER   RESOURCES   OP    CALIFORNIA. 


PARDEE  RESERVOIR  ON  MOKELUMNE  RIVER. 

UNUSED  SPACE  WHILE  CONTROLLING  TWENTY  LARGEST  RAIN  WATER 

FLOODS  OF  RECORD  BY  RESERVOIR  OPERATING 

DIAGRAM,  1904-1926. 

Reservoir  Operated   Coordinately    for    Municipal    Supply    with    Incidental 

Power,  and  Flood  Control. 

Height  of  dam  345  feet.  Capacity  of  reservoir  222,000  acre-feet. 


Maximum  flood  flow — 

uncontrolled 

Flow  controlled  to  5,300  second-feet  maximun.  near  Clements 

Reservoir  space  not  used  in 

Mean  daily  flow 

controlling  flood 

In  per  cent  of 

Date 

near  Clements 

Date  reservoir  nearest  full 

in  3econd-feet 

In  acre-feet 

maximum  space 
required  for 
flood  control 
(92,000  acre- 
feet) 

Jan.  30,  1911 

16,700 

Feb.    1,  1911 

35.200 

38 

Mar.  19,  1907 

15,310 

Mar.  27,  1907 

7,100 

8 

Jan.  26, 1914 

11,100 

Jan.  27,  1914 

68,900 

75 

Jan.   14,  1909 

10,400 

Jan.   17.  1909 

19,500 

21 

Feb.  21,  1914 

9,850 

Feb.  21,  1914 

82,700 

90 

Feb.    e,  1925 

9,700 

Feb.    6,1925 

167,800 

182 

Jan.     1,  1914 

9,250 

Jan.     1,  1914 

82,000 

89 

Jan.  21,  1909 

8,400 

Jan.  22,  1909 

8,500 

9 

Mar.  20,  1916 

8,040 

Mar.  21,  1910 

64,400 

70 

Feb.    2,  1907 

7,860 

Feb.    4, 1P07 

79,300 

86 

Mar.  31,  1906 

7,750 

April   1,  1906 

49,600 

54 

Mar.  23, 1907 

7,610 

Mar.  27,  1907 

7,100 

8 

Jan.  22,  1914 

7,470 

Jan.  22, 1914 

78,600 

85 

Jan.  18,  1921 

7,350 

Jan.  18,  1921 

75,700 

82 

Mar.   7,  1911 

7,210 

Mar.  11,  1911 

70,900 

77 

Nov.  21,  1909 

7,200 

Nov.  21,  1909 

68,300 

74 

Feb.  11,  1919 

7,060 

Feb.  11,  1919 

90,4C0 

98 

Jan.  19,  1906 

6,960 

Jan.    19,  1900 

76,400 

83 

Mar.  12, 1918 

6,940 

Mar.  12,  1918 

109,600 

119 

Aprilie,  1925 

6,910 

April  17,  1925 

6,600 

7 

Average 

62,400 

68 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


201 


PARDEE  RESERVOIR  ON  MOKELUMNE  RIVER. 
UNUSED  SPACE  WHILE  CONTROLLING  ALL  SNOW  WATER  FLOODS  OF 

RECORD  BY  RESERVOIR  OPERATING  DIAGRAM,  1904-1926. 
Reservoir    Operated    Coordinately    for    Municipal    Supply    with    Incidental 

Power,  and  Flood  Control. 
Height  of  dam  345  feet.  Capacity  of  reservoir  222,000  acre-feet. 


Maximum  flood  flow- 

uncontrolled 

Flow  controlled  to  7,100  second-feet  maximum  near  Clements 

Reservoir  space  not  used  in 

Mean  daily  flow 

controlling  flood 

In  per  cent  of 

Date 

near  Clements 

Date  reservoir  nearest  full 

in  second-feet 

In  acre-feet 

maximum  space 
required  for 
flood  control 
(13,000  acre- 
feet) 

June  12,  1906 

8,740 

June  13,  1906 

1,900 

15 

June  18,  1911 

8,030 

June  18, 1911 

3,300 

25 

June    3,  1922 

7,970 

June    5,  1922 

2,600 

20 

June  12, 1911 

7,960 

June  12, 1911 

3,100 

24 

June    6,1911 

7,880 

June    6,  1911 

4,000 

31 

May  31,  1922 

7,770 

June    1,  1922 

6,700 

52 

June    1,  1915 

7,750 

June    1,  1915 

10,000 

77 

May  18,  1922 

7,670 

May  19,  1922 

1,800 

14 

June  16,  1906 

7,600 

June  17,  1906 

4,500 

35 

June  10,  1917 

7,550 

Jane  10,  1917 

2,900 

22 

May  24,  1911 

7,500 

May  24,  1911 

800 

6 

July    4,  1906 

7,480 

July     4,  1906 

1,100 

8 

Average 

3,000 

28 

13-5:^111 


202 


WATER   RESOURCES   OP   CALIFORNIA. 


TEMPERANCE  FLAT  RESERVOIR  ON  SAN  JOAQUIN  RIVER. 
UNUSED  SPACE  WHILE  CONTROLLING  ALL  RAIN  WATER  FLOODS  OF 

RECORD  BY  RESERVOIR  OPERATING  DIAGRAM,  1907-1926. 
Reservoir  Operated  Coordinately  for  Irrigation  with  Incidental  Power,  and 

Flood  Control. 
Height  of  dam  595  feet.  Capacity  of  reservoir  1,071,000  acre-feet. 


Maximum  flood  flow- 

uncontrolled 

Flow  controlled  to  10,700  second-feet  maximum  near  Friant 

Reservoir  spice  net  used  in 

Moan  daily  flow 

controlling  flood 

In  per  cent  of 

maximum  space 

required  for 

flood  control 

Date 

near  Friant  in 
second-feet 

Date  reser vol  r  nearest  full 

In  acre-feet 

(133,000  acre- 

feet) 

Jan.   31,  1911 

38,800 

Feb.     1,  1911 

538,000 

405 

Dec.  31,  1909 

27,900 

Jan.     1,  1910 

260,300 

196 

Jan.   14,  1909 

26,800 

Jan.   15,  1909 

853,400 

642 

Dec.  10,  1909 

26,800 

Dec.  10,  1909 

418,100 

314 

Jan.   26,  1914 

24,700 

Jan.  26,  1914 

811,700 

610 

Jan.   21,  1909 

18,900 

Jan.  22,  1909 

751,400 

565 

Mar.   8,  1911 

18,800 

Mar.   8,  1911 

344,700 

259 

Mar.  10,  1911 

13,600 

Mar.  10,  1911 

310,200 

233 

Feb.  12,  1909 

12,500 

Feb.  12,  1909 

631,800 

475 

Feb.  21,  1917 

11,700 

Feb.  21,  1917 

321,700 

242 

April  6,  1911 

11,600 

April   6,  1911 

141,900 

107 

Jan.    18,  1916 

11,000 

Jan.   18,  1916 

414,500 

312 

Mar. 21,  1916 

11,000 

Mar.  21,  1916 

74,500 

56 

Oct.     2,  1918 

10,900 

Oct.     2,  1918 

775,000 

583 

Jan.  25,  1911 

10,700 

Jan.  25,  1911 

735,900 

553 

Average 

492,200 

370 

THE    CONTROL   OF   FLOODS   BY   RESERVOIRS. 


203 


TEMPERANCE  FLAT  RESERVOIR  ON  SAN  JOAQUIN  RIVER. 
UNUSED   SPACE  WHILE   CONTROLLING  ALL  SNOW   WATER   FLOODS 

OF  RECORD  BY  RESERVOIR  OPERATING  DIAGRAM  1907-1926. 
Reservoir  Operated  Coordinately  for  Irrigation  with  Incidental  Power,  and 

Flood  Control. 
Height  of  dam  595  feet.  Capacity  of  reservoir  1,071,000  acre-feet. 


Maximum  flood  flow- 

uncontrolled 

Flow  controlled  to  14,200  second-feet  maximum  near  Friant 

Reservo'r  space  not  used  in 

Mean  daily  flow 

controlling  flord 

In  percent  of 

Date 

near  Friant  in 

Date  reservoir  nearest  full 

second-feet 

Id  acre-feet 

maximum  space 
required  for 
flood  control 

(177,000  acre- 

feet) 

June  13,  1911 

23,100 

Jane  23,  1911 

21,100 

12 

Jane    4,  1909 

22,800 

June    8 

1909 

89,100 

50 

June  IG,  1911 

21,500 

June  23 

1911 

21,100 

12 

July     7,  1911 

19,500 

Julv     7 

1911 

57,600 

33 

June    5,  1922 

16,700 

June    8 

1922 

417,100 

236 

May  22,  1911 

16,200 

May  23 

1911 

134,600 

76 

June    6,  1911 

16,200 

June    8 

1911 

165,500 

94 

May    8,  1909 

16,200 

May    8 

1909 

308,800 

174 

June    2,  1914 

15,700 

June    2 

1914 

167,500 

95 

June    5,  1912 

15,300 

June    5 

1912 

526,400 

297 

June  15,  1909 

14,900 

June  15 

1909 

95,000 

54 

June  27,  1911 

14,700 

June  28 

1911 

38,290 

22 

May  31,  1922 

14,700 

June    1 

1922 

575,000 

325 

June  24,  1909 

14,600 

June  24 

1909 

129,300 

73 

Average 

196,200 

111 

204 


WATER  RESOURCES   OF   CALIFORNIA. 


SAN  GABRIEL  RESERVOIR  ON  SAN  GABRIEL  RIVER. 
UNUSED  SPACE  WHILE  CONTROLLING  TWENTY  LARGEST  FLOODS  OF 

RECORD  BY  RESERVOIR  OPERATING  DIAGRAM,  1895-1926. 
Reservoir  Operated  Coordinately  for  Flood  Control,  Seasonal  and  Over-year 

Storage. 
Height  of  dam  383  feet.  Capacity  of  reservoir  180,000  acre-feet. 


Maximam  flood  flow- 

uncontrolled 

Flow  controlled  to  1,900  second-feet  maximum  near  Aziisa 

Reservcir  sp.ce  not  used  in 

Mean  daily  flow 
near  Azusa  in 

Date  reservoir  nearest  full 

CO  itroiling  flood 

Date 

In  per  cent  of 

second-feet 

In  acre-feet 

maximum  space 
reiiuircd  for 
flood  control 

(131,000  acre- 

feet) 

Jan.   18,  1916 

22,300 

Jan.  20,  1916 

50,800 

39 

Dec.  19,  1921 

16,000 

Dec.  25,  1921 

71,800 

55 

Jan.     1,  1910 

12,500 

Jan.     3,  1910 

89,000 

68 

Fe)).  20,  1914 

11,800 

Mar.    1,  1914 

64,500 

49 

Mar.  12,  1905 

11,130 

Mar.  14,  1905 

94,000 

72 

Mar.  26,  1906 

9,430 

Mar.  29,  1906 

32,600 

25 

Mar.  10,  1911 

9,160 

Mar.  14,  1911 

71,400 

54 

Jan.  26,  1914 

9,150 

Jan.  27,  1914 

111,600 

85 

Feb.    9.  1922 

8,200 

Feb.  13,  1922 

104,300 

SO 

Mar.  12,  1906 

8,020 

Mar.  13,  1906 

103,400 

79 

Jan.  27,  19 IG 

7,940 

Jan.  30,  1916 

42,600 

33 

Feb.     7,  1909 

7,100 

Feb.    8,  1909 

118,100 

90 

Mar.   5,  1907 

6,810 

Mar.  11,  1907 

89,900 

69 

April   1,  190.3 

5,920 

April  2,  1903 

137,700 

105 

Dec.  27,  1921 

5,900 

Dec.  29,  1921 

53,700 

41 

Jan.  29,  1911 

5,260 

Jan.  29,  1911 

126,600 

97 

Jan.   !8,  1914 

5,110 

Jan.   18,  1914 

125,600 

96 

Mar.  11,  1918 

5,030 

Mar.  14,  1918 

91,500 

70 

Jar.   10,  1907 

4,670 

Jan.   11,  1907 

110,900 

85 

Jan.  31,  1911 

4,220 

Jan.  31,  1911 

122,400 

93 

Average 

90,600 

69 

The  full  tests  are  expressed  graphically  on  Plate  XXVII,  "Per- 
formance of  Reservoir  Operating  Diagrams  in  Controlling  Floods  of 
Record  Coordinately  with  Conservation."  The  ratio  of  the  empty 
reservoir  space  while  controlling  floods  coordinately  with  conservation 
as  described  herein,  to  that  actually  necessary  for  control  of  the 
remainder  of  the  flood  was  computed  for  eveiy  day  of  stream  flow 
record  on  each  of  the  four  illustrative  stream^s.  The  ratios  on  each 
stream  were  arranged  in  order  of  increasing  magnitude  and  the  number 
smaller  than  each  successive  size  counted.  These  counts  were  increased 
by  pi'oportion  to  the  number  had  the  stream  flow  records  been  100 
years  in  length,  and  plotted  on  Plate  XXVII.  Smooth  curves  were 
drawn  which  indicate  the  ])r()hal)l('  frcupiency  with  which  the  empty 
space  on  hand  at  any  time  Avill  approach  the  exact  amount  that  should 
be  on  hand  to  insure  the  desired  flood  regulation.  Superimposed  on 
these  are  dashed-line  curves  transposed  from  Plate  XXII,  p.  96. 
These  indicate  the  corres})onding  relations  in  controlling  floods  when 
not  coordinated  with  conservation. 

('omparison  is  made  in  the  following  table  of  the  probable  number 
rtf  days  in  ]0()  years  on  which  empty  s})a('<'  equal  to  or  greater  than 
the  exact  amount  rccpiired  for  controlling  floods  would  be  provided  in 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


205 

PLATE   XXMI. 


1 

(0 

KENNETT  RESERVOIR 

0> 

ON  SACRAMENTO  RIVER 

Capacity  2.940,000  ac.  ft. 

lU 

M 

1 — 

- 

--t—                    17'iOOO  ^er,  ft                     1 

■(5 

F 

— 1- 

" 

^ 

^Reservoir  operated  coordmately  for 
Irrigation  with  incidental  power  and 

Lt- 

"Reservoir  operated  for  flood  control 
alone,  taken  from  Plate  MS. 

{2 

§ 

— 

— 

— 

o 

o 

-lU- 

\\ 

c 

\ 

V 

tn 

\\ 

^ 

\ 

V 

\ 

•s 

^ 

— 

— 

— 

-'' 



L. 
<1> 

f= 

100^ 

=s 

:^ 



3 

— ' 

— 

— 

— 

PARDEE  RESERVOIR 

ON  t^OKELUMNE  RIVER 

Capacity  2??,000  ac  ft 

— 

— 

-.  

•    Ram  water  floods  5300  sec  ft 

—  1- 

-   Snowwater  floods 7,100  sec  ft. 
—Reservoir  operated  coordinatel>  for 

municipal  supply  with  incidental  power 

v    " 

alor 

e,  ta 

,n  Irom  t^lateAJUi.      1 

— , 

- 

— 1 

-J 

= 

X 

-10- 

" 

" 

j 

ii\ 

1   1 

i\\ 

T 

\  v 

Snow  water  floods        -4- 
dentical  for  both           _^ 

1  \ 

V 

/|r 

^ 

^1^ 

pMg^ ■"',"','' .  1 1  :| 

■lUU- 

II        _ 

^y 

^:: 

---. 

1  i: 

Rain  water  floods^ 

■' 

'::>.. 

Iv 

r-i 

•-  res 

— 

— ' 



— 

— 

0.1 


100  0.1 


100 


^  = 


SA 

N  GABRIEL  RESERVOIR 

ON  SAN  GABRIEL  RIVER 

Capacity   180,000  ac  ft. 

— 

1,900  sec.  ft. 

-1- 

1          " 

eservoir  operated  coordinate!/  for 
ood  control,  constant  draft  of  72 
ec.ft  and  variable  summer  drafts 
rom  seasonal  storage. 

1  1      f 

1  i___„ 

eservoir  operated  for  flood  control 
one,  taken  from  Plate  XXn. 

'  1      ^ 

-lU- 

1  1 
1   w 
1    L 
1    I 

1    I 

« 

* 

1 ..     . 

I — VV- 

1 



•100- 

- 

1    1 

".\ 

\ 

~ 

N 

^  _ 

t 

,  s 

•■■ 

», 

mk 

4= 

!<.i^i 

TEMPERANCE  FLAT  RESERVOIR] 

ON  SAN  JOAQUIN  RIVER 

Capacity  1,071, 000  ac  ft 

1 

•  Rain  water  floods  I0,700sec.ft. 

-1- 

.. 

"  Snow  water  floods  I4,200secft. 
—  Reservoir  operated  coordinately  for 

irrigation  with  incidental  power  and 
flood  control. 

■"Reservoir  operated  for  flood  control 

0 

alone,  taken  from  Plate. 

JU.  . 

■ 1 



— 

— 

\\0- 

t\ 

1 

l\ 

V 

\ 

\ 

N 

am  water  floods 

4^*^ 

\. 

*•* 

■  — .fc,^ 

f 

■"-" 

- 

^ 

^^ 

»i     1 

-- 

^—{■ 



"■**n 

=s« 

!rrt-  = 

I    -t+t 

— 

U  '  ^ 

I — rr~j'"/ 

it 

-"-4— « 

;      1  ; 

= 

== 

fIJIII     II  1141 

:::^==44:fe;1 

I  10  100   I  10  100 

Ratio  of  reservoir  space  provided  to  that  actually  required. 


1000 


Performance  of  Reservoir  Operating  Diagrams  in  Controlling 
Floods  of  Record  Coordinately  with  Conservation 


CURVES   SHOW  NUMBER  OF  DAYS  IN  100  YEARS  ON  WHICH 

RATIO  OF  RESERVOIR  SPACE  PROVIDED  BY  APPLICATION  OF 

DIAGRAM  TO  THAT  ACTUALLY  REQUIRED   FOR  CONTROLLING 

FLOODS  OF  RECORD  IS  SMALLER  THAN  INDICATED. 


206 


WATER  RESOURCES   OP   CALIFORNIA. 


the  two  instances.  The  probable  frequency  with  which  the  dasired 
controlled  flow  would  be  exceeded  downstream  from  the  Kennett  res- 
ervoir on  the  Sacramento  Eiver,  would  be  raised  by  coordination  with 
conservation  as  described  herein,  from  about  one  day  in  80  to  one  day 
in  100  years ;  downstream  from  the  Pardee  reservoir  from  about  one 
day  in  40  to  one  day  in  50  years  for  rain-water  floods  with  no  change 
for  snow-water  floods;  downstream  from  the  Temperance  Flat  reser- 
voir from  about  one  day  in  30  to  one  day  in  more  than  1000  years  for 
rain-water  floods,  but  with  no  change  for  snow-water  floods ;  and  below 
the  San  Gabriel  reservoir  the  frequency  with  w^hich  the  desired  con- 
trolled flow  may  be  exceeded  would  be  increased  from  one  day  in  500 
to  one  day  in  more  than  1000  years. 


PROBABLE    FREQUENCY    WITH    WHICH    LESS    EMPTY    SPACE    THAN 

FROM  ONE  TO  TWO  TIMES  THE  EXACT  AMOUNT  REQUIRED  TO 

CONTROL  FLOODS  WILL  BE  PROVIDED. 

(Frequency  in  number  of  days  in  100  years) . 


Fioud  control  coordinated  with  conser- 
vation as  described  in  Chapter  VI 

Flood  control  as  described  in  Chapter  V, 
not  coordinated  with  conservation 

Rsservoiras  described  horcin 

Equal  to 

that 
required 

Half  again 

that 
required 

Twice  that 
required 

Equal  to 

that 
required 

Half  again 

that 
required 

Twice  that 
required 

Kennett 

1 

2  0 
2.5 

I.CFS  than  0. 1 
3.2 

9 

40 
24 

Less  than  0.1 
100 

40 

20 

70 
50 

Lees  than  0.1 
150 

50 

1.2 

2.5 

2  5 

3  2 
3.2 

0  5 

12 

GO 
24 

43 
100 

50 

30 

Pardee— 

Rain-water  floods 

100 

Snow-water  floods 

50 

Temperance  Flat- 
Rain-water  floods 

70 

Snow-water  floods 

150 

San  Gabriel 

120 

THE   CONTROL   OP   FLOODS   BY   RESERVOIRS.  207 


CHAPTER  VII. 


CONCLUSIONS. 

Reliability  of  analyses. 

The  system  of  flood  analysis  herein  described,  illustrated,  and  tested 
is  entirely  empirical.  Although  it  is  in  accord  with  theoretic  considera- 
tions, nevertheless,  it  does  not  rest  upon  hypothesis  but  rather  is 
deduced  directly  from  the  past  behavior  of  floods  as  shown  by  the 
records  of  their  measurement.  But  one  assumption  is  employed, 
namely,  that  whatever  relation  that  may  exist  between  the  time  of 
year,  the  occasion  and  the  size  of  flood  occurrence,  should  be  contained 
within  existing  stream-flow  data.  In  order  to  discover  this  relation, 
the  usual  distinction  between  flood  and  normal  flow  is  omitted.  The 
relation  between  time  of  year,  occasion  and  size  of  occurrence  is  sought 
for  flows  of  all  magnitudes  contained  in  the  measured  record  with  the 
expectancy  that  this  relation,  when  found,  may  be  extended  to  disclose 
the  circumstances  under  which  flows  of  extraordinary  size  may  occur, 
flows  larger  than  are  contained  within  the  stream  flow  records  or  are 
evidenced  by  high  water  marks  or  dimensions  of  existing  flood  channels. 
In  seeking  this  relation  interest  is  not  centered  in  average  occurrences 
as  in  many  engineering  investigations,  but  rather  in  the  limiting  con- 
ditions of  flood  occurrence.  The  safety  of  lives  and  property  require 
that  works  for  flood  protection  be  designed  for  exceptional  rather  than 
average  conditions,  otherwise,  the  flood  menace  would  not  be  removed. 
Therefore,  the  analyses  take  the  form  of  discussions  of  the  frequency 
with  which  various  size  flows  occur  at  different  times  of  the  year  and 
with  different  amounts  of  seasonal  precipitation  up  to  the  time  of 
their  occurrence. 

The  limiting  conditions  of  flood  occurrence  about  which  knowledge 
is  desired,  are  the  circumstances  under  which  the  very  infrequent 
flood,s  occur.  The  limits  in  time  of  year  and  in  the  amount  of  previous 
rainfall  with  which  extraordinary  stream  discharge  occurs,  are  sought 
through  the  development  of  curves  expressing  the  average  frequency 
of  past  occurrences.  It  was  found  by  trial  that  the  data  expressing 
the  relation  between  size  of  flow  and  average  frequency  of  its  occur- 
rence plot  on  fairly  smooth  curves  of  similar  shape  for  all  California 
streams  on  which  continuous  measurements  have  been  made.  While 
most  of  the  data  from  which  these  curves  are  developed  concern 
ordinary  events,  as  they  happen  less  frequently  they  approach  the 
extraordinary.  By  the  extension  of  these  curves  beyond  the  limits  of 
the  plotted  data,  the  frequency  may  be  anticipated  of  events  so 
extraordinary  that  not  even  a  single  one  is  contained  within  the  period 
of  record.     By  this  system  of  graphical  analysis,  estimate  is  made  of 


208  WATER   RESOURCES   OF    CALIFORNIA. 

Avhat  the  records  Avould  disclose  were  they  many  times  longer  than 
they  actually  are.* 

The  inclusion  in  these  anah'ses  of  all  data  on  stream  discharge 
without  distinction  between  flood  and  normal  flow  multiplies  many 
times  the  number  of  data  available  to  guide  the  drafting  of  curves  of 
relationship.  In  a  record  of  stream  flow,  say  thirty  years  long,  there 
may  be  from  three  to  six  thousand  entries  of  daily  flow  while  the 
entries  customarily  regarded  as  floods  may  be  limited  to  perhaps  from 
fifteen  to  thirty.  Thus,  in  the  system  of  analyses  herein  employed,  a 
large  volume  of  data  defines  with  considerable  certainty  that  part  of 
the  curves  of  relationship  pertaining  to  usual  occurrences  so  that  the 
trend  of  the  curves  is  established  as  they  approach  the  zones  of 
infrequent  occurrence  into  which  they  are  extended. 

AVhether  or  not  stream  discharge  follows  sufficiently  definite  rules 
to  warrant  the  close  consideration  herein  given  was  seriously  questioned 
at  the  time  the  Avork  was  started.  For  this  reason,  the  first  eft'ort  held 
to  a  comparatively  simple  scheme  of  analysis.  Working  with  an  appre- 
ciation that  the  subject  is  not  one  favorable  for  exactness,  two  efforts 
were  made  before  the  subject  could  be  adequately  gauged.  While  a 
casual  review  of  the  work  as  finally  completed  is  not  entirely  convincing 
that  the  great  volume  of  detail  with  which  the  subject  has  been  pursued, 
is  warranted,  yet,  to  those  who  have  taken  part  in  the  intricate  com- 
parisons, it  became  evident  before  proceeding  very  far.  that  much  of 
the  apparent  scattering  of  plotted  points  on  the  diagrams  is  the  result 
of  the  small  amount  of  data  on  infrequent  flows  contained  in  the  com- 
paratively short  period  of  stream  flow  record  in  California,  rather 
than  of  inconsistencies  in  relationship.  The  relationship  under  study 
pertains  only  to  the  average  frequency  of  occurrence  without  regard  to 
the  sequence  of  events,  so  that,  in  plotting  the  data,  frequencies  were 
assigned  neces.saril}-  based  upon  the  number  of  times  events  occurred 
within  the  period  of  measured  record.     The  infrequent  events  that 

*  Inasmuch  a.s  thi.s  entire  work  is  an  analysis  of  the  historical  trend  of  flood 
occurrence,  as  disclosed  by  the  period  of  measured  stream  flow  record,  it  is  of 
mterest  to  discover  if  possible  to  what  extent  discordant  events  may  be  expected  to 
occur.  In  reviewing  this  possibility  among  rainfall  data  that  antedate  stream  flow 
records  by  some  30  or  40  years,  it  was  observed  that  the  sea.sons  18S3-4  and  1889-90 
m  southern  California  were  very  unusual.  Both  had  more  than  double  normal 
precipitation  while  the  largest  season  during  the  period  of  measured  run-off  had 
barely  .50  per  cent  more  than  normal  precipitation.  Also  the  season  1883-4,  as  dis- 
closed by  the  records  at  Los  Angeles,  was  unusual  in  having  a  storm  of  2.32  inches 
in  two  day.s  during  the  fore  part  of  April,  while  the  season  1889-90  was  extremely 
unusual  in  the  volume  of  fall  precipitation,  it  aggregating  by  January  1,  1890.  62  per 
cent  in  excess  of  the  total  for  a  normal  season.  A  detail  study  of  the  daily  precipita- 
tion of  these  two  seasons  shows  that,  had  the  reservoir  operating  diagram  for  the 
San  Gabriel  River  been  in  use,  there  might  have  been  technical  failure  in  its  operation 
by  the  reservoir  filling  and  some  water  passing  over  the  spillway  to  augment  the 
rontrolled  flow  below  the  reservoir,  however,  no  reason  was  found  to  suppose  that 
this  quantity  would  have  been  large  enough  to  be  serious.  It  is  evident  from  study- 
ing the  records  that  both  of  these  seasons  had  unusual  features  that  depart  materially 
from  the  trend  of  the  period  of  measured  run-off  so  that  some  modification  of  the 
reservoir  operating  diagram  for  the  San  Gabriel  River,  as  herein  presented,  would 
probably  be  required  if  it  were  desired  that  the  operation  of  the  diagram  be  tech- 
nically perfect  in  these  two  seasons  and  run-off  records  were  at  hand  to  work  with. 

Run-off  data  collected  on  the  four  illustrative  streams  since  the  close  of  the 
analyses  contained  in  this  bulletin  have  also  been  reviewed  for  discordant  events. 
It  was  found  that  all  floods,  including  that  of  March  2.'')-27,  1928,  would  have  been 
controlled  as  anticipated.  The  flood  of  March  25-27.  19  28,  on  the  Mokelumne  River, 
however,  exceeded  the  once-in-SO-year  value  which,  by  construction,  the  diagram  is 
not  expected  to  control.  Therefore,  the  empty  space  provided  by  the  diagram  fails 
to  control  this  flood  under  direct  test.  Nevertheless,  with  flood  control  and  conserva- 
tion coordinated  as  described  herein,  this  flood  would  have  been  controlled  to  the 
specified  maximum  flow  by  reason  of  the  additional  empty  space  provided  by  the 
drawdown  resulting  from  normal  conservation  draft. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS.  209 

occur  but  once  or  twice  within  the  period  of  record,  are  thus  accorded 
an  average  standing  that  may  or  may  not  be  actually  theirs.  It  is 
apparent  that  the  occurrence  of  these  infrequent  events  within  the. 
years  during  which  stream  flow  measurements  happened  to  be  made, 
is  much  a  matter  of  circumstance  since  there  appears  to  be  no  orderly 
sequence  in  the  size  of  stream  flow.  When  longer  records  of  stream  flow 
become  available,  no  doubt  many  of  these  events  will  be  found  to  per- 
tain to  quite  different  average  intervals  than  those  herein  assigned. 
With  this  viewpoint  in  mind,  positions  on  the  diagrams  were  found  for 
the  curves  and  parts  of  curves  representing  infrequent  events  that  are 
logical  in  relation  to  the  plotted  data  but  that  appear  in  places  to  be 
out  of  sympathy  with  some  of  them.  Whether  or  not  the  interpretations 
are  correct  can  not  be  foretold.  Greater  length  of  stream  flow  record 
alone  can  furnish  the  means  of  improving  these  interpretations  of  the 
data.  In  the  meantime  the  results  of  the  analyses  should  be  employed 
Avith  judgment. 

The  four  reservoir  operating  diagrams,  constructed  as  a  conclusion 
of  the  anal.yses  described  herein,  are  tested  against  the  entire  period 
of  stream-flow  record  on  their  respective  streams  at  the  close  of  Chap- 
ters V  and  VI  and  are  found  to  be  entirely  adequate  for  controlling 
all  floods  of  record.  In  fact,  for  the  most  part,  more  than  half  the 
space  provided  by  the  diagrams  for  detaining  excess  flood  water  is 
seldom  used  in  these  tests.  Even  the  largest  floods  of  record  do  not 
require  the  entire  reserve  to  detain  their  volume  of  excessive  flow. 
Although  in  engineering  practice,  test  against  the  period  of  record  is 
often  deemed  sufficient  to  determine  the  reliability  of  performance  of 
proposed  control  w^orks,  nevertheless,  it  is  thought  that  a  particular 
advantage  of  the  system  of  analysis  herein  described  is  that  it  affords 
the  means  of  designing  flood  control  works  not  only  adequate  for  all 
occurrences  of  historical  record  but  adequate,  to  the  degree  selected, 
for  future  expectancies  as  disclosed  by  the  trend  of  the  historical  record. 
It  is  of  interest  to  note,  for  instance,  in  connection  with  the  reservoir 
operating  diagram  for  controlling  floods  on  the  San  Gabriel  River 
when  employed  in  the  "Coordinated  Plan,"  that  only  three-fifths  of 
the  131,000  acre-feet  of  maximum  flood  control  reserve  is  filled  while 
controlling  the  largest  flood  of  record  to  1900  second-feet,  and  that  only 
one-third  of  this  maximum  reserve  is  filled  on  an  average  in  so  control- 
ling the  twenty  largest  recorded  floods.  This  reservoir  operating  dia- 
gram was  designed  to  control  floods  larger  than  have  occurred  wdthin 
the  period  of  record.  For  this  reason  the  floods  of  record  do  not  fill 
the  entire  reserve.  A  safety  factor  either  greater  or  less  than  indicated 
l)y  the  above  figures  could  have  been  introduced  in  the  diagram  at  tlie 
time  of  its  construction  if  it  were  thought  desirable. 

In  response  to  the  question  as  to  what  would  happen  if  several  large 
floods  should  follow  one  another,  the  largest  flood  of  record  in  each 
calendar  month  from  December  to  April  on  the  San  Gabriel  River  was 
selected  and  they  were  assumed  to  follow  one  another,  each  occurring 
on  its  actual  calendar  date  under  the  conditions  of  recorded  precipita- 
tion but  transposed  to  a  hypothetical  year.  The  transposition  was 
made  from  one  year  to  the  other  on  the  day  before  the  first  rapid 
increase  in  flow  of  the  next  flood.    By  test  against  this  series  of  floods, 


210  WATER   RESOURCES   OF    CALIFORNIA. 

the  San  Gabriel  diagram  was  thus  found  to  be  adequate  to  control  in 
succession  the  floods  of  December,  1921,  January,  1916,  February,  1914, 
March,  1905,  and  April,  1926. 

It  may  be  concluded,  therefore,  that  the  reliability  of  the  system  of 
analyses  herein  described  is  essentially  dependent  upon  the  extent  to 
which  the  future  will  repeat  the  past.  If  it  does  and  the  years  of 
stream  flow  record  at  hand  disclose  the  past  correctly,  then  the  deduc- 
tions of  these  analyses  are  reliable.  If  it  does  not,  the  deductions 
involve  the  same  error  that  is  contained  in  all  other  hydraulic  estimates 
of  common  use.  The  foundation  of  all  engineering  rests  upon  the 
expectancy  of  a  repetition  of  past  events  under  like  circumstances  in 
the  future.  Many  millions  of  dollars  are  spent  annually  and  whole 
cities  are  erected  upon  this  assumption.  Without  it  practical  engineer- 
ing could  not  progress.  The  nineteen  to  thirty-one  years  of  stream  flow 
measurement  upon  which  the  illustrations  of  this  volume  are  based, 
furnish  a  longer  record  than  is  available  in  many  instances  for 
hydraulic  design.  The  lack  of  data  often  makes  it  necessary  to  base 
hydraulic  design  on  rather  brief  stream  flow  records  and  sometimes 
none  at  all.  Because  these  illustrations  are  based  upon  the  longest 
records  of  stream  flow  in  the  state,  it  is  believed  that  they  have  a 
stronger  claim  for  accuracy  than  most  work  of  the  kinrl.  Therefore, 
the  analyses  of  this  volume  are  presented  as  illustrative  of  principles 
relating  to  the  control  of  floods  by  reservoirs  adequately  reliable  in 
their  essential  features  for  practical  application,  if  judgment  is 
employed.  Although  the  reservoir  operating  diagrams  are  presented 
as  a  culmination  to  these  analyses,  nevertheless,  it  is  not  intended  that 
their  features  should  be  applied  indiscriminately.  They  are  presented 
as  illustrations  and  their  features  should  be  adjusted  to  the  necessities 
of  each  specific  instance  in  order  to  secure  good  results. 

Accuracy   of   analyses. 

p]ssentially  speaking,  the  accuracy  of  the  analyses  contained  herein 
is  dependent  upon  the  correctness  of  the  rainfall  and  stream  gaging 
records  employed.  It  is  commonly  known  that  the  cost  of  gaging 
streams  with  exactness  is  prohibitive  for  general  work.  On  the  other 
hand,  experience  in  ('alifornia  indicates  that  for  the  most  part,  the 
records  of  the  United  States  Geological  Survey  that  have  been  used 
exclusively  in  this  work,  are  substantially  correct.  To  .seriously  affect 
the  analyses  there  would  have  to  be  an  error  in  either  tiie  observations 
of  rainfall  or  stream  flow  continuing  through  years  of  time,  or  in  the 
i-ecords  of  the  larger  floods  that  east  the  greater  influence  in  the  exten- 
sion of  the  curves  of  the  several  diagrams.  This  volume  is  prepared 
with  full  acceptance  of  the  stream  gaging  and  rainfall  records  as  pub- 
lished or  in  pi-ei)ai-ation  for  publication  by  the  federal  bureaus.  It  has 
been  left  to  the  judgment  of  whoever  may  utilize  its  cont(>nts,  to  intro- 
duce such  safety  factor  in  this  res])ect  as  may  be  deemed  desirable 
under  the  circumstances  at  the  time  of  use.  Attention  has  been  ]ilaced 
on  ])io  lucing  a  woi'k  thai  would  mak(>  tliis  |)ossible. 

Effect  of  length  of  stream  flow  record   upon  the  accuracy  of  deductions. 

In  reviewing  the  analyses  described  in  this  volume,  it  may  seem 
rather  bold  to  at1<'iiipt  to  ])i-('di('t  tlie  vast   future  from  tlie  trend  of 


THE    CONTROL   OF    FLOODS   BY    RESERVOIRS.  211 

occurrences  during  the  past  15  to  30  years,  yet,  there  appears  to  be 
no  alternative,  if  such  knowledge  is  desired,  until  sufficient  time  has 
elapsed  from  the  beginning  of  systematic  records  for  the  accumulation 
of  more  data.  Systematic  measurements  of  California  streams  started 
in  1895,  only  thirty-two  years  ago.  It  was  some  time,  however,  before 
many  streams  were  included  in  the  program,  so  that  there  are  now  only 
a  few  that  have  been  measured  for  more  than  twenty  years.  Fortu- 
nately, as  closer  settlement  and  larger  property  values  urge  greater 
accuracy  in  flood  analysis  than  can  be  attained  at  present,  the  expe- 
rience of  additional  years  will  be  at  hand  for  more  perfect  analyses 
than  .can  be  attained  with  present  information.  In  the  meantime, 
judgment  must  be  employed  in  the  application  of  the  best  analyses 
possible  of  available  data. 

In  order  to  throw  some  light  upon  the  extent  to  which  the  length  of 
stream  flow  record  affects  the  required  reservoir  space  for  controlling 
floods  indicated  by  these  analyses,  Plate  XXVIII,  ' '  Effect  of  Omission 
of  the  First  Half  of  the  Years  of  Record  that  Contains  Five  of  the 
Largest  Floods  on  Indicated  Reservoir  Space  Required  to  Control 
Floods  on  Sacramento  River  near  Red  Bluff,"  has  been  prepared.  It 
illustrates  the  variance  in  deductions  that  may  be  made  from  two 
records,  one  half  the  length  of  the  other  and  containing  only  the  lesser 
floods.  The  anah'sis  .shown  in  black  is  taken  from  Plate  X  of  Chapter 
IV.  It  employ's  the  entire  thirty  years  of  record  on  the  Sacramento 
River.  Superimposed  in  red  is  an  analysis  of  the  last  fifteen  years, 
similar  in  all  respects  to  the  first  except  that  it  employs  only  the  half 
of  the  record  subsequent  to  the  historic  flood  years  of  1907  and  1909. 

It  may  be  observed,  in  the  part  of  the  plate  relating  to  the  data  used 
in  constructing  Plate  XVIII,  "Reservoir  Operating  Diagram  for  Con- 
trolling Floods  on  the  Sacramento  River,"  that  the  difference  in  the 
maximum  flood  control  reserve  determined  by  these  two  analyses,  is 
15  per  cent. 

Geographical   limitations  of  system   of  analysis. 

Since  the  entire  analysis  herein  presented  is  empirical  and  has  been 
developed  and  tested  entirelj^  from  data  on  California  streams,  it  is  not 
known  to  w^hat  extent  it  may  be  successfully  applied  in  other  localities. 
No  doubt  the  definite  limits  to  the  flood  season  found  in  these  analj'ses 
bear  some  relation  to  the  sharp  demarcation  between  the  wet  and  dry 
seasons,  one  of  the  distinctive  features  of  California  climate.  Since 
this  distinct  wet  and  dry  season  is  the  reason  for  conserving  flood 
waters  in  California,  it  seems  probable  that  the  double  use  of  the  same 
reservoir  space  for  both  flood  control  and  conservation  Avould  not  be  of 
such  economic  importance  if  climatic  conditions  were  different.  There- 
fore, it  can  not  be  said,  without  extended  inquiry  which  has  not  been 
made,  to  what  extent  the  system  of  analyses  herein  described  applies 
to  localities  of  less  marked  wet  and  dry  seasons  than  California.  The 
discussion  herein  presented  is  of  California  conditions. 

Future  possibilities  of  improving  proposals  for  control  of  floods  by  reservoirs. 

The  proposals  for  controlling  floods  by  reservoirs  described  herein 
all  pertain  to  single  reservoirs.  At  the  time  of  preparing  this  work,  a 
large  program  of  reservoir  construction  is  in  its  inception  in  California. 


212  WATER   RESOURCES   OF   CALIFORNIA, 


PLATE  X.W'III, 


Reservoir  space  in  per  cent  of 
greatest  daily  run-off  of  once-in-25-year  flood 

(493,800  acre  feet)          _               - 

—                      o                      o 

3                                                                    _                                 O                                O                                O 
-                                 —                                O                                O                                O                                CK 

Nu 
.1 

mber 

of  da 
1 

ys  in 

OOjyearsc 

10 

)n  whic 

100 

n  reservoir 

1,000 

space  is  exceedec 

10,000            100 

=  ,     _     !  Maximum  controlled  t  low 

000 

E 

'     °75^rffl5e»nd.eef 

■■             10            24,900 
20            49,800 
30            74,700 

o            40            99,600 
50           124,500 

'^            60           149,400 
70          174,300 

-.-. 

■:::=  =  =  . 

"4—. 



--^  =  =  = 

";;;'^s 

"^-a.; 

!s;i 1 — 1   1  1  1 1  rn 1 — i—i-rrrn 

--•  10%-HVIaximum  controlled  flow 

"^^v. 

». 

-  '^^ 

■■»i»i 

""*^»« 

^v 

In 

N 

fei 

iii5 

=  ?-: 

l  T 

> 

^0 

f.l 

N- 

4--^^;= 

S"^^""^ 

-!f^l 

zzt 

M  \ 

N^ 

'i  ^^   '**^ 

;  M-i^d> 

\  \ 

-!v^^. 

I'A 

V            ^ 

— - 

1 

1 

I---  p 

R 

=  : 

:-:-: 

\t 

\70^ 

1 



-4^' 

1         1 

— - 

---  .. 

"       ± 

— : 

— ,  .. 

Indicatee 

Effect  of  Omission 

OF   THE 

First  Half  of  the  Years  of  Record 
^T  Contains  Five  of  the  Largest  Floods 

ON 

)  Reservoir  Space  Required  to  Control  Flo( 

3DS 

ON  Sacramento  River  near  Red  Bluff 

BLACK   CURVES -ANALYSIS  OF  RECORDS    1895  TO  1925 
RED  CURVES- ANALYSIS  OF  RECORDS    1910  TO  1925  (FLOODS  OF  1904,1907  AND  1909   OMITTED) 

CURVES    SHOW   NUMBER   OF  DAYS    IN  100   YEARS    ON   WHICH 

RESERVOIR   SPACE   GREATER  THAN    INDICATED  IS  NEEDED 

TO    CONTROL  FLOODS    TO    SPECIFIED   MAXIMUM    FLOW. 

Maximum  controlled  flow  expressed  in  per  cent  of  greatest  daWy  rate  cfflow  of  a  once-in-25-^ear  flood 

i411— Page   :ill' 


THE    CONTROL   OF    FLOODS   BY    RESERVOIRS.  213 

Since  this  program  must  necessarily  be  constructed  progressively,  the 
possibility  of  coordinating  flood  control  by  reservoirs  and  conservation 
is  illustrated  herein  in  its  relation  to  the  first  installment  of  this  large 
reservoir  construction  program.  The  examples  worked  out  demonstrate 
that  the  first  units  of  this  large  reservoir  construction  program  may  be 
used  to  control  floods  without  interference  with  conservation  values. 
However,  as  time  goes  on  and  more  than  one  large  reservoir  is  con- 
structed on  each  stream,  the  flood  control  reserve  may  be  divided 
among  several  reservoirs  instead  of  being  allocated  entirely  to  one  as 
in  the  illustrations  herein.  In  doing  this,  either  a  greater  degree  of 
flood  control  may  be  efiPected  by  enlarging  the  total  reserve  or  the 
possibility  of  interference  with  conservation  may  be  made  even  more 
remote  than  in  the  proposals  herein  described  and  tested  by  dividing 
the  reserve  without  enlargement  among  several  reservoirs. 

The  proposals  for  the  control  of  floods  by  reservoirs  may  be  still 
further  improved  as  years  pass  by,  since  stream  flow  data  covering 
longer  periods  of  time  will  be  at  hand.  The  added  data  will  permit 
new  analyses  to  be  made  that  will  offer  greater  assurance  of  accuracy 
than  is  possible  at  present  and  through  closer  study  made  possible  by 
additional  data,  no  doubt  improvements  may  be  devised  in  the  con- 
struction of  the  reservoir  operating  diagrams.  It  is  certain  that  much 
improvement  may  be  made  in  the  part  of  the  diagrams  pertaining  to 
snow-water  floods. 

In  the  analysis  herein,  the  part  of  the  diagrams  pertaining  to  snow- 
water floods  is  constructed  using  indices  of  rainfall.  Since  snow-water 
floods  pertain  more  to  the  amount  of  snow-on-the-ground  at  any  time, 
rather  than  upon  the  total  of  previous  seasonal  precipitation,  it  is  evi- 
dent that,  were  data  of  snow-on-the-ground  available,  superior  results 
could  be  obtained.  This  is  indicated  on  Plate  XXIV,  p.  119,  and  Plate 
XXV,  p.  131,  which  show  the  effect  on  reservoir  stage  of  controlling 
floods  on  the  Mokelumne  and  San  Joaquin  rivers  by  the  reservoir 
operating  diagrams  described  in  Chapter  V.  In  reviewing  these  plates, 
it  is  noticeable  in  many  instances,  that  space  is  held  in  reserve  for 
flood  control  during  the  latter  part  of  June  and  the  first  part  of  July, 
when,  by  the  indications  of  subsequent  stream  flow,  the  snow  in  the 
mountains  must  have  been  too  far  melted  to  produce  floods.  Since  these 
reservations  of  reservoir  space  are  held  nearly  to  the  close  of  the  run-off 
season,  they  result  in  the  reservoir  failing  to  fill  to  the  point  that  it 
otherwise  would,  had  space  not  been  reserved  for  flood  control,  and 
cause  a  slightly  reduced  yield  thereby.  While  in  these  two  instances 
the  differences  in  reservoir  yield  with  and  without  flood  control  are 
small,  nevertheless,  it  is  believed  that  a  noticeable  improvement  could 
be  made  in  the  part  of  the  work  relating  to  snow-water  floods,  if  data 
relating  to  snow-on-the-ground  were  available.  It  is  believed  that 
superior  results  could  be  obtained  by  constructing  the  pai't  of  the 
reservoir  operating  diagram  relating  to  snow-water  floods  upon  indices 
of  snow-on-the-ground  instead  of  upon  indices  of  precipitation.  The 
rainfall  indices  apparently  indicate  the  general  character  of  the  season 
fairly  well  so  far  as  rain-water  floods  are  concerned,  but,  in  failing  to 
incorporate  the  effect  of  weather  conditions  subsequent  to  precipitation 
upon  the  amount  of  unmelted  snow  remaining  on  the  ground,  lead  to 
the  unnecessary  reservation  of  reservoir  space  for  the  control  of  snow- 


214  WATER   RESOURCES   OF   CALIFORNIA. 

water  floods  almost  up  to  the  close  of  the  run-off  season.  If  indices  of 
snow-on-the-!?round  at  some  suitable  mountain  .station  were  used  both 
in  consti-uctinj?  and  a])i)lying  the  pai't  of  the  reservoir  operating  dia- 
grams relating  to  snow-water  floods,  the  Pardee  and  Temperance  Flat 
reservoirs  undoubtedly  would  have  filled  to  the  .same  point  each  year 
both  with  and  without  flood  control  and  there  would  not  have  been 
even  the  slight  reduction  in  reservoir  yield  with  the  inclusion  of  flood 
control  that  is  noted  in  the  tests  of  the  reservoir  operating  diagrams  on 
the.se  two  streams.     (See  pp.  121  and  130.) 

Indices  of  snow-on-the-ground  could  not  be  used  in  constructing  the 
reservoir  operating  diagrams  for  the  Mokelumne  and  San  Joaquin 
rivers  because  records  suitable  for  this  purpose  are  not  available.  So 
far  as  known,  the  only  records  of  snow-on-the-ground  of  anj^  length  are 
at  points  in  the  Sacramento  River  drainage  basin.  Since  snow  melts 
earlier  in  the  season  in  the  Sacramento  than  in  the  San  Joaquin  basin, 
these  records  are  not  adapted  for  use  on  the  Mokelumne  and  San 
Joaquin   rivers. 


THE   CONTROL   OP    FLOODS   BY    RESERVOIRS.  215 


CHAPTER  VIII. 


TABLES  OF  MONTHLY  SUMMARIES  OF  WATER  AND  POWER 
YIELD  OF  RESERVOIRS  ON  THE  FOUR  ILLUSTRATIVE 
STREAMS. 

Yield  computed  on  a  daily  basis  to  show  the  effect  of  inclusion  of 
the  flood  control  feature  upon  the  yield  of  the  "Coordinated  Plan." 

KENNETT   RESERVOIR  ON   SACRAMENTO    RIVER. 

Table       Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 
No.  Page 

Assumptions  employed  in  computing  water  and  power  yield 216 

la.     Operating    primarily    for    power    generation    with    incidental    irrigation. 

With  and  without  flood  control  by  reservoir  operating  diagram 218 

2a.     Operating    primarily    for    irrigation    with    incidental    power    generation. 

With  and  without  flood  control  by  reservoir  operating  diagram 234 

3a.     Operating  primarily  for  irrigation.     Comparison  for  two  methods  of  flood 

control 250 

4a.     Operating    primarily    for    power    generation    with    incidental    irrigation. 

Comparison  for  two  methods  of  flood  control 266 

5a.     Summary  of  power  yield.    With  and  without  two  methods  of  flood  control  282 

PARDEE   RESERVOIR  ON    MOKELUMNE   RIVER. 

Height  of  dam  345  feet.     Capacity  of  reservoir  222,000  acre-feet. 

Assumptions  employed  in  computing  water  and  power  yield 298 

6a.     Yield  with  and  without  flood  control  by  reservoir  operating  diagram 300 

7a.     Comparison  of  yield  for  two  methods  of  flood  control 312 

8a.     Summary  of  yield  in  water  and  power  with  and  without  flood  control 324 

TEMPERANCE    FLAT    RESERVOIR    ON    SAN    JOAQUIN    RIVER. 

Height  of  dam  595  feet.    Capacity  of  reservoir  1,071,000  acre-feet. 

Assumptions  employed  in  computing  water  and  power  yield 331 

9a.     Yield  with  and  witliout  flood  control  by  reservoir  operating  diagram 332 

10a.     Comparison  of  yield  for  two  methods  of  flood  control 342 

11a.     Summary  of  yield  in  water  and  power 352 

SAN  GABRIEL  RESERVOIR  ON   SAN   GABRIEL   RIVER. 

Heights  of  dams  383  and  425  feet.     Capacity  of  reservoirs  180,000  and  240,000 

acre-feet. 

Assumptions  employed  in  computing  water  yield 358 

12a.     Yield   under   "Coordinated   Plan."      Flood   control   and   seasonal   storage 

coordinated.     Capacity  180  000  and  240,000  acre-feet 360 

13a.     Yield  under  "Coordinated  Plan."     Flood  control  and  seasonal  and  bvei'- 

year  storage  coordinated.     Capacity  ISO.OOO  and  240,000  acre-feet 382 

15a.  Comparison  of  yield  for  two  methods  of  flood  control.  Flood  control 
coordinated  with  seasonal  and  over-year  storage.  Capacity  180,000 
acre-feet    404 

IGa.     Comparison  of  yield  for  three  steps  in  coordinating  the  use  of  reservoir 

space.    Capacity  180,000  acre-feet 426 

17a.     Comparison  of  yield  operating  for  flood  control  and  constant  draft  only. 

Capacity  180,000  and  240,000  acre-feet 448 


216  WATER   RESOURCES   OF   CALIFORNIA. 

ASSUMPTIONS  EMPLOYED  IN  COMPUTING  WATER  AND  POWER  YIELD 
OF  KENNETT  RESERVOIR  ON  SACRAMENTO  RIVER  ON  DAILY  BASIS. 

1.  Water  supply  at  dam  site  is  the  flow  at  the  Ked  Bhiif  gaging 
station  of  the  United  States  Geological  Survey  unimpaired  by  upstream 
diversions,  less  25.9  per  cent  which  is  estimated  to  originate  on  the 
average  on  the  drainage  area  between  the  dam  site  and  gaging  station, 
and  less  the  unimpaired  flow  of  the  Pit  River  at  Bieber.  No  deductions 
are  made  for  prior  rights  downstream  from  the  dam. 

2.  Daily  stream  flow  at  the  dam  site  on  any  day  within  a  month 
bears  the  same  relation  to  the  monthly  mean  at  the  dam  site  as  the 
measured  mean  daily  discharge  of  the  same  date  at  the  Red  Bluff 
gaging  station  of  the  United  States  Geological  Survey  bears  to  the 
corresponding  measured  monthly  mean  at  this  station. 

3.  The  reservoir  is  full  on  June  1,  1895,  the  opening  date  of  the 
estimates.  Run-off  index  of  season  1894-1895  is  12-4.  The  reservoir 
fills  in  1925  with  a  run-off  index  of  81. 

4.  The  net  evaporation  from  the  reservoir  surface  equals  3.5  feet 
depth  per  annum,  divided  among  the  months  as  follows : 

Depth  in  Per  cent  of 

Month  feet  seasonal  total 

April    0.32  9.2 

May    0.44  12.G 

June 0.52  15.0 

July   0.62  17.8 

August 0.58  16.6 

September 0.45  12.7 

October    0.34  9.6 

November    0.23  6.5 

3.50  100.0 

5.  The  total  seasonal  demand  for  irrigation  water  is  divided  among 
(he  months  as  follows: 

Demand  in  per 
cent  of  total 
Month  seasonal  use 

January  0 

February    0 

March    1 

April 0 

May    16 

June 20 

July   22 

August 20 

September 12 

October    4 

November    0 

December    0 

Total   100 

6.  The  seasonal  irrigation  yield  is  that  which  can  be  obtained  during 
the  period  witii  a  deficiency  on  the  average  not  oftener  than  one  year 
in  ten. 

7.  Power  is  generated  at  a  plant  near  the  base  of  the  dam  with  a 
power  factor  of  0.80  and  load  factors  as  noted. 


THE   CONTROL   OF   P'LOODS   BY    RESERVOIRS.  217 

8    Primary  power  yield  is  the  eneroy  that  can  be  generated  without 
fail  through  every  season  from  1871  to  1926,  divided  among  the  months 

as   lOilOWS  :  Electric  power  con- 

sumption in  per 
cent  of  annual 
total  (state- wide 

i,r     *T  average) 

Month  r-  o 

Januai-y ~~"~  q'^j 

February    ~  ^  8 

March ,j-'g 

April ZZIIIIIZIIII  8  8 

May    -__-       -   _  9;o 

June    __  ^4 

July c)5 

August    g^Y 

September    g',^ 

October g'g 

November g"o 

December   '2, 

„,  ,  T  .  100.00 

Total 

9  The  secondary  power  vield  is  the  energy  that  can  be  generated 
intermittently  by  the  installed  capacity  of  the  power  plant  m  addition 
to  the  primary  output.  ,    .  n 

10  The  overall  plant  efficiency  is  75.0  per  cent  at  full  reservoir 
level,  increases  to  77.4  per  cent  at  0.8  depth  and  then  decreases  to  75.0 
per  cent  at  0.6  depth  of  a  full  reservoir.  ,,,r.r.nf^  i 

11  The  elevation  of  the  tail  race  rises  26  feet  when  100,000  second- 
feet  are  passing  the  dam,  17  feet  when  50,000  second-feet  are  passing, 
10  feet  when  25,000  second-feet  are  passing  and  corresponding  amounts 
for  other  floAvs.  '  ' 


14—52411 


218 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  la.     KENNETT  RESER 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 
Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Esti- 
mated 
run-off 

Wifhouf  flocd  control 

Year  and 
month 

Stage  of 

Power  dr.ift 

.\verage  power 

yield 

at 
dam 

reservoir 
at 

through  turbines  in 
acr!-feet 

Evapora- 

Waste 
over 

.Average 

in  kilowatts 
(Load  factcr~0.75) 

site 

in 

acre-feet 

beginning 

of 
month  in 
acre-feet 

tion  in 
acre-feet 

spillway 

in 
acre-feet 

power 

head  in 

feet 

Primary 

Secondary 

♦Primary 

Sscondgry 

Total 

1896 

Jan. 

1,980,000 

2,256,000 

238,000 

98,030 

0 

960,000 

389 

97.400 

40,500 

137.900 

Feb. 

474,000 

2,940,000 

218,000 

173.000 

0 

83,000 

408 

98.400 

78.000 

176,400 

Mar. 

738,000 

2,940,000 

245,000 

21.5.000 

0 

278,000 

410 

101,200 

91,100 

195,300 

April 

891,000 

2,940,000 

249,000 

231,000 

7,000 

404,000 

408 

109,000 

101.000 

210,000 

May 

1,194,000 

2,940,000 

279,000 

219,000 

10,000 

68'J.OOO 

407 

117,500 

92.500 

210,000 

June 

53'i,000 

2,940,000 

283,000 

196,000 

12,000 

80,000 

410 

124,200 

85.800 

210,000 

July 

313,000 

2,905,000 

298,000 

151,000 

14.000 

0 

407 

125,400 

63.700 

189.100 

Aug. 

268,000 

2,755,000 

301,000 

102,000 

13,000 

0 

400 

126,700 

42.500 

169,200 

Sept. 

258,000 

2,604,000 

282,000 

101,000 

10,000 

0 

394 

120,000 

42,800 

162.800 

Oct. 

282,000 

2,469.000 

278,000 

75.000 

7,000 

0 

388 

113,400 

3  3,. =00 

143.' 03 

Nov. 

472,000 

2,371,000 

264,000 

161,000 

5,000 

0 

385 

110,300 

63.800 

177.100 

Dec. 

Total  or 
average 

920,000 

2,413,000 

267,000 

246,000 

0 

0 

392 

109,400 

100.600 

210,000 

8,306,000 

3,205,000 

1,968,000 

78,000 

2,491000 

400 

113,000 

69,500 

182.500 

1897 

Jan. 

577,000 

2,820,000 

220,000 

129  000 

0 

99,000 

412 

97,400 

55,000 

152,400 

Feb. 

1,338,000 

2,940,000 

218,000 

231,000 

0 

889,000 

408 

101.900 

108.100 

210,000 

Mar. 

737,000 

2,940.000 

247,000 

251,000 

0 

23:1,000 

407 

104.200 

105.800 

210,000 

April 

8.58,000 

2,940,000 

249,000 

231.000 

7,000 

371,000 

408 

109.000 

101.000 

210,000 

May 

551,000 

2,940,000 

276,000 

195,000 

10,000 

73,000 

411 

117.500 

82.500 

200,000 

June 

310,000 

2,940,000 

283,000 

73.000 

12,000 

0 

410 

121.200 

32.100 

156.300 

July 

2/5,000 

2,882.000 

298,000 

90.000 

14,000 

0 

407 

125,400 

37.900 

163.300 

Aug. 

254  000 

2,755.000 

305,000 

87.000 

13,000 

0 

400 

126,700 

3"),200 

162.900 

Sept. 

247,000 

2,604.000 

282,000 

90,000 

10,000 

0 

394 

120,000 

38,200 

1.58.200 

Oct. 

262,000 

2,469,000 

278.000 

75,00(1 

7,000 

0 

388 

113,400 

39.500 

143,900 

Nov. 

274,000 

2.371,000 

265.000 

97,000 

5,000 

0 

382 

110,300 

40.300 

1.50,600 

Dec. 
Total  or 
average 

366,000 

2,278,000 

274,000 
3.204.000 

113,000 

0 

0 
1,671,000 

380 
401 

10.9,400 
113,400 

45.200 

154,600 

6,052,000 

1,662,000 

78,000 

59,100 

172,500 

1898 

Jan. 

257,000 

2,2,57,000 

213,000 

(1 

(1 

0 

380 

97,400 

0 

97,400 

Feb. 

478,000 

2,271,000 

226.000 

(1 

0 

0 

388 

101.900 

0 

101, '.00 

Mar. 

380,000 

2.523,000 

218,000 

0 

0 

0 

397 

104,200 

0 

101.200 

April 

274,000 

2,655,000 

253,000 

0 

7,000 

0 

400 

109.000 

0 

109.000 

May 

300,000 

2,669,000 

281,000 

(1 

10,000 

0 

401 

117.500 

0 

117.500 

June 

301,000 

2.678,000 

287,000 

0 

11,000 

0 

401 

121,200 

0 

124,200 

July 

237,000 

2,681,00(1 

301,000 

0 

14.000 

0 

400 

125,400 

0 

125,400 

Aug. 

225,000 

2,606,00(1 

307,000 

(1 

12.000 

0 

316 

126.700 

0 

126,700 

Sept. 

198,000 

2,512,000 

2St.()(IO 

0 

9,000 

0 

390 

120.000 

0 

120,000 

Oct. 

221,000 

2,417,000 

279,000 

(1 

7,00(1 

0 

386 

113.400 

0 

113,400 

Nov. 

217,000 

2,352  000 

265,000 

21,000 

5,000 

0 

383 

1 10.300 

8,890 

119,100 

Dec. 
Total  or 
average 

217,000 
3,308,000 

2.278.000 

274.000 
3,248,000 

0 
21.000 

0 

0 

380 
392 

109.400 
113,400 

0 
700 

109.400 

75.000 

0 

114.190 

1899 

Jan. 

605.000 

2,221,000 

23.1,000 

(1 

0 

0 

388 

97,400 

0 

97,400 

Feb. 

253.000 

2.587,000 

222,000 

(1 

0 

0 

398 

101,900 

0 

ioi,roo 

Mar. 

900,000 

2,618,000 

219,000 

65,000 

0 

264,000 

404 

104,200 

27.300 

131.500 

April 

456,000 

2,940,000 

217,000 

174.000 

7,000 

28,000 

411 

109,000 

76,300 

185.300 

May 

330,000 

2.940.000 

276.000 

44.000 

10.000 

0 

412 

117,500 

18.800 

13 -..300 

June 

302,00(1 

2,910,000 

'JS'.'.OOO 

5'),011(l 

12,000 

7,000 

411 

121.200 

25.700 

149.900 

July 

210.000 

•>  SS2.000 

218.000 

5.i,0(l(l 

1  1,00(1 

0 

407 

125,400 

23.100 

118.500 

Aug. 

221,000 

2,7.55,000 

301,000 

5H,000 

13  0011 

0 

400 

126,700 

21.200 

1.50.900 

Sept. 

197,000 

2.601,000 

282.000 

40,000 

10.000 

0 

394 

120,090 

16.900 

13).  000 

Oct. 

252.000 

2.469.000 

278  00(1 

65.000 

7  00(1 

0 

388 

113,400 

2i,.500 

131.C00 

Nov. 

645.000 

2.371.000 

261.000 

187,000 

5,000 

0 

381 

110  300 

77.900 

188  200 

Dec. 
Total  or 
average 

646,000 
5,0.50,000 

2,560,000 

265,000 

243.000 
990,000 

0 
78.000 

0 

299,000 

398 

400 

109.400 

100,600 

210,000 

3,206,000 

113.400 

31,900 

148,300 

♦Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


219 


VOIR  ON  SACRAMENTO  RIVER. 

POWER  GENERATION   WITH   INCIDENTAL   IRRIGATION 

BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  1,  page  108.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.  F.  =  0.80 


Coordinated  with  flood  control  by  reservoir 

operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125 

000  sec.-ft 

Alaximum  reservcnr  space  required  4o4.000 

ac.-ft. 

Stage  of 

reservoir 

at 

Power  draft 

through  turbines  in 

acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Average 

power 

head  in 

feet 

Average  power  yield 

in  kilowatts 
(Load  factor^O.75) 

Year  and 
month 

of 
month  in 
acre-feet 

Primar.v 

Secondarj- 

♦Primary 

Secondary 

Total 

1896 

2,256,000 

242.000 

118.000 

0 

1.357,000 

0 

383 

97,400 

47,200 

144.600 

Jan. 

2,509,000 

231.000 

51,000 

0 

50,000 

0 

396 

98,400 

22.300 

120.(00 

Feb. 

2,651,000 

247.000 

49,000 

0 

0 

153.000 

405 

104,200 

20,400 

124.600 

Mar. 

2.940.000 

249.000 

231,000 

7.000 

0 

404,000 

408 

109,000 

101,000 

210,000 

April 

2,940.000 

279,000 

219.000 

10.000 

0 

686.000 

407 

117,500 

92,500 

210.000 

May 

2,940.000 

283.000 

196.000 

12.000 

0 

80.000 

410 

124,200 

85,800 

210,000 

June 

2,905,000 

238.000 

151.000 

14.000 

0 

0 

407 

125,400 

63,700 

183.100 

July 

2  755.000 

304.000 

102.000 

13.000 

0 

0 

400 

126,700 

42,500 

169.200 

Aug. 

2,604,000 

282,000 

101.000 

10.000 

0 

0 

394 

120,000 

42,800 

162,800 

Sept. 

2.46,1,000 

278,000 

75,000 

7.000 

0 

0 

388 

113,400 

30,500 

143,900 

Oct. 

2,371.000 

264.000 

161,000 

5.000 

0 

0 

385 

110,300 

66.800 

177.100 

Nov. 

2,413.000 

268,000 

247,000 

0 

223,000 

0 

330 

109,400 

100,600 

210.000 

Total  or 

3.225,000 

1,701,000 

78,000 

1,640,000 

1,323.000 

398 

113,000 

59,700 

172,700 

average 
1897 

2.595.000 

238,000 

174,000 

0 

252.000 

0 

o92 

97,400 

71,000 

168,400 

Jan. 

2..508,000 

228.000 

242.000 

0 

846.000 

0 

385 

101,900 

108,100 

210,000 

Feb. 

2.530.000 

251.090 

130.000 

0 

75,000 

0 

398 

104,200 

53,200 

157,400 

Mar. 

2.811,000 

249.000 

186,000 

7,000 

2.000 

285.000 

408 

109,000 

81,400 

190,400 

^r'' 

2  940,000 

276.000 

195,000 

10  000 

0 

73.000 

411 

117,500 

82.500 

200.000 

May 

2.940,000 

283.000 

73.000 

12.000 

0 

0 

410 

124,200 

32,100 

156.300 

June 

2.882.000 

298.000 

90,000 

14.000 

0 

0 

407 

125.400 

37,900 

163.300 

July 

2,755.000 

305.000 

87.000 

13.000 

0 

0 

400 

126,700 

38.200 

162.900 

Aug. 

2  604.000 

282,000 

90,000 

10.000 

0 

0 

334 

120,000 

38,200 

158.200 

Sept. 

2,469,000 

278.000 

75.000 

7.000 

0 

0 

388 

113,400 

30..500 

143.900 

2,371,000 

265.000 

97.000 

5,000 

0 

0 

382 

110,300 

40,300 

150,600 

Nov. 

2,278,000 

274.000 

113.000 

0 

0 

0 

380 

109,400 

45.200 

154,600 

Total  or 

3,227,000 

1,552,000 

78,000 

1.175,000 

358,000 

396 

113,400 

54,300 

167,700 

average 

2,257,000 

243,000 

0 

0 

0 

0 

380 

97,400 

0 

97,400 

1898 

Jan. 

2,271,000 

226,000 

0 

0 

0 

0 

388 

101,900 

0 

101,900 

Feb. 

2.523.000 

248,000 

0 

0 

0 

0 

337 

104,200 

0 

104,200 

Mar. 

2,655.000 

253,000 

0 

7,000 

0 

0 

400 

109,000 

0 

109,000 

April 

2,669,000 

281,000 

0 

10,000 

0 

0 

401 

117,500 

0 

117,500 

May 

2,678,000 

287.000 

0 

11,000 

0 

0 

401 

124,200 

0 

124,200 

June 

2,684,000 

301.000 

0 

14.000 

0 

0 

400 

125.400 

0 

125,400 

July 

2,606.000 

307.000 

0 

12.000 

0 

0 

336 

126,700 

0 

126,700 

Aug. 

2,512,000 

284.000 

0 

9.000 

0 

0 

330 

120,000 

0 

120.000 

Sept. 

2.417.000 

279.000 

0 

7.000 

0 

0 

386 

113,400 

0 

113.400 

Oct. 

2.352,000 

265.000 

21,000 

5.000 

0 

0 

383 

110,300 

8,800 

119.100 

Nov. 

2,278,000 

274.000 

0 

0 

0 

0 

380 

109,400 

0 

109.400 

Dec. 
Total  or 

3,248,000 

21.000 

75.000 

0 

0 

392 

113.400 

700 

114.100 

avcrjge 
1899 

2,221,000 

241,000 

45.000 

0 

2,000 

0 

387 

97,400 

18,400 

115.800 

Jan. 

2.538,000 

223,000 

0 

0 

0 

0 

396 

101,900 

0 

101.900 

Feb. 

2.568,000 

219.000 

57.000 

0 

278.000 

0 

399 

104,200 

23.900 

128.100 

Mar. 

2,884,00C 

246  OCO 

140.000 

7.000 

0 

7,000 

412 

103,000 

61.500 

170.500 

April 

2,940,00(] 

276.000 

44.000 

10.000 

0 

0 

412 

117..500 

18.800 

136.300 

May 

2,940,O0C 

282.000 

53.000 

12.000 

0 

7,000 

411 

124,200 

25.700 

149.900 

June 

2.882,0!)C 

298.000 

55.000 

14.000 

0 

0 

407 

125,400 

23.100 

148.500 

July 

2,755.000 

304.000 

58.000 

13.000 

0 

0 

400 

126,700 

21.200 

150.900 

Aug. 

2.604.09C 

282.000 

40,000 

10,000 

0 

0 

334 

120,000 

16.900 

136.100 

Sept. 

2.469.00f 

278.000 

65,000 

7.000 

0 

0 

388 

113,400 

26.500 

139.900 

Oct. 

2.371,O0C 

264.000 

187.000 

5,000 

0 

0 

386 

110..300 

77.900 

188.200 

Nov. 

2.550.000 

266.000 

244.00) 
994.000 

0 

108.000 

0 

396 
399 

103.400 

100.600 

210.000 
148.400 

Dec. 

Total  or 

3,203.000 

78.000 

388.000 

14,000 

113.40r 

35.000 

average 

220 


WATER   RESOURCES   OF   CALIFORNIA. 


TABLE  la  (Continued).     KENNETT 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresfxjnding  yearly  sum 

Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Without  flood  control 

Esti- 
mated 

Year  and 
month 

run-off 

Stage  of 

Power  draft 

Average  power 

yield 

at 

reservoir 

through  turbines  in 

Waste 

.\verage 

n  kilowatts 

dam 

at 

acre-feet 

Evapora- 

over 

(Load  factor=0.75) 

site 

in 

acre-feet 

beginning 

of 
month  in 
acre-feet 

tion  in 
acre-feet 

spillway 

in 
acre-feet 

power 

head  in 

feet 

Primary 

Secondary 

•Primarj- 

Secondary 

Total 

1900 

Jan. 

1,299,000 

2,698.000 

232.000 

247.000 

0 

578.000 

405 

97,400 

103.500 

200.900 

Feb. 

391.000 

2.910.000 

217.000 

134.000 

0 

40.000 

410 

101,900 

62.500 

164.400 

Mar. 

912.000 

2,940.000 

245.000 

242000 

0 

425.000 

410 

104.200 

102.400 

206.600 

April 

457,000 

2.940,000 

246.000 

183.000 

7,000 

21.000 

412 

109.000 

80.300 

189,300 

May 

413,000 

2.940.000 

276,000 

110.000 

10.000 

17.000 

412 

117,500 

46.600 

164,100 

June 

247,000 

2.940.000 

282,000 

11.000 

12,000 

0 

412 

124,200 

4.900 

129  100 

July 

219.000 

2,882.000 

297.000 

35,000 

14,000 

0 

408 

125.400 

14.800 

140,200 

Aug. 

208,000 

2.755.000 

303.000 

43.000 

13.000 

0 

402 

126.700 

17.900 

144.600 

Sept. 

201.000 

2.604.000 

282.000 

44.000 

10.000 

0 

394 

120.000 

18.800 

138.800 

Oct. 

508,000 

2.469,000 

278.000 

121  000 

7.000 

0 

.388 

11S.400 

49,200 

162.600 

Nov. 

368.000 

2,371.000 

2fi-l.000 

145.000 

5,000 

0 

384 

110.300 

59,700 

170.000 

Dec. 

697.000 

2.325.000 

271,000 

222,000 

0 

0 

384 

109.400 

89,000 

198,400 

Total  or 

average 

5,720,000 

3,193,000 

1,537,000 

78,000 

1,081,000 

402 

113,400 

54,200 

167,600 

1901 

Jan. 

895.000 

2.529.000 

230,000 

95.000 

0 

159.000 

406 

97.400 

39.900 

137,300 

Feb. 

1.304.000 

2.940,000 

218,000 

223.000 

0 

863.000 

408 

101.900 

104,200 

206.100 

Mar. 

749.000 

2.940.000 

247,000 

246.000 

0 

256.000 

407 

104.200 

103,800 

208.000 

April 

382,000 

2.940.000 

246,000 

123.000 

7,000 

6.000 

412 

109.000 

54,000 

163.000 

May 

411,000 

2,940.000 

276,000 

120.000 

10,000 

5,000 

412 

117,500 

51,100 

168.600 

June 

240,000 

2.940.000 

282,000 

4.000 

12,000 

0 

412 

124.200 

1,800 

126,000 

July 

218,000 

2.882.000 

297,000 

34.000 

14.000 

0 

408 

12.-,400 

14,200 

139.600 

Aug. 

206.000 

2.755.000 

303,000 

41.000 

13.000 

0 

402 

126.700 

17,100 

143.800 

Sept. 

200.000 

2,604.000 

282.000 

43.000 

10.000 

0 

394 

120.000 

18,200 

138.200 

Oct. 

21.5.000 

2.460.000 

278,000 

28.000 

7.000 

0 

388 

113.400 

11,400 

124.800 

Nov. 

354.000 

2.371.000 

265,000 

103.000 

5,000 

0 

383 

110.300 

42.500 

152.800 

Dec. 

550.000 

2,352,000 

272,000 

252,000 

0 

0 

383 

109,400 

100,600 

210.000 

Total  or 

average 

5,724.000 

3,196.000 

1.312.000 

78,000 

1,289.000 

401 

113,400 

46,300 

159,700 

1902 

Jan. 

227,000 

2.378,000 

240.000 

0 

0 

0 

386 

97,400 

0 

97,400 

Feb. 

2.782.000 

2,365,000 

224.000 

153.000 

0 

1,830,000 

392 

101,900 

69.300 

171,200 

Mar. 

1.11.5.000 

2,940,000 

218.000 

253.000 

0 

614,000 

404 

104.200 

105.800 

210,000 

April 

801,000 

2.940.0OO 

249.000 

232.000 

7,000 

403,000 

408 

109.000 

101.000 

210.000 

May 

765.000 

2.940.000 

278.000 

216,000 

10,000 

261,000 

409 

117.500 

91.400 

208,900 

June 

407.000 

2.940.000 

282.000 

164,000 

12,000 

7,000 

410 

124.200 

71.700 

195,900 

July 

2,54,000 

2.882,000 

2<i8.000 

69.000 

14.000 

0 

406 

125.400 

29,000 

154.400 

Aug. 

234.000 

2,755,000 

304.000 

68,000 

13.000 

0 

400 

126,700 

28.400 

1.55,100 

Sept. 

184.000 

2,604,000 

282.000 

27,000 

10.000 

0 

394 

120.000 

11,400 

131.400 

Oct. 

235,000 

2,469,000 

278.000 

48,000 

7.000 

0 

388 

113,400 

19,500 

132,900 

Nov. 

829.000 

2.371.000 

258.000 

190,000 

5.000 

0 

396 

110.300 

81.100 

191,400 

Dec. 
Total  or 
average 

762.000 

2,747,000 

260,000 

239,000 

0 

70,000 

407 

109,400 

100,600 

210,000 

8,685,000 

3,201.000 

1,659,000 

78,000 

3.185,000 

400 

113,400 

58.900 

172.300 

1903 

Jan. 

1,113,000 

2,940,000 

2.;0.000 

214,000 

0 

669,000 

409 

97,400 

90.300 

187,700 

Feb. 

633.000 

2,940,000 

218.000 

231,000 

0 

184,000 

408 

101.900 

108,100 

210.000 

Mar. 

1,339.000 

2,940.000 

246.000 

252,000 

0 

841.000 

408 

104.200 

105,800 

210.000 

April 

765.000 

2.940.000 

250,000 

232.000 

7,000 

276.000 

407 

109.000 

101,000 

210.000 

May 

458,000 

2.940.000 

276.000 

152,000 

10,000 

20,000 

412 

117,500 

64,700 

182,200 

June 

278,000 

2.940.000 

282.000 

42,000 

12.000 

0 

412 

121.200 

18.300 

142.500 

July 

231,000 

2,882,000 

297.000 

47.000 

14.000 

0 

408 

125,400 

19.800 

145.200 

Aug. 

204.000 

2,7.55.000 

303.000 

39.000 

13.000 

0 

402 

126,700 

16.300 

143.000 

Sept. 

174,000 

2.604.000 

282.000 

17.000 

10.000 

0 

394 

120,000 

7.200 

127.200 

Oct. 

199,000 

2.469.000 

278.000 

12.000 

7.000 

0 

388 

113.400 

4.800 

118,200 

Nov. 

924.000 

2.371.000 

261,000 

156.000 

5,000 

0 

390 

110,300 

65,600 

17.5.900 

Dec. 
ToUl  or 
average 

530,000 

2,873.000 

259,000 

238,000 

0 

0 

408 

109.400 

100,600 

210,000 

6.848,000 

3,18'?,000 

1.632,000 

78,000 

1,990.000 

404 

113,400 

58,200 

171,600 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  ir.  other  years. 


THE    CONTROL   OP   FLOODS   BY    RESERVOIRS. 

RESERVOIR  ON  SACRAMENTO  RIVER. 

POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 

BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  I,  page  108.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


221 


P.P.  =  0.80 


Coordinated  with  flood  control  by  reservol 

operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-f 

.    Maximum  reservoir  space  required  454,000  ac.-ft. 

Stage  of 

Power  draft 

.\verage  power  1 

•ield 

reservoir 

through  turbines  in 

Release 

Waste 

in  kilowatts 

at 

acre-feet 

Evapora- 

through 

over 

Average 

(Load  factor=C 

.75) 

Year  and 

beginning 

tion  in 
acre-feet 

flood 
control 

spillway 
in 

power 
head  in 

month 

of 

month  in 

outletsin 

acre-feet 

feet 

acre-feet 

Primary 

Secondary 

acre-feet 

'Primary 

Secondary 

Total 

2.588,000 

240,000 

274.000 

0 

883,000 

0 

388 

97,400 

110,900 

208,300 

1900 

Jan. 

2.490,000 

224.000 

49,000 

0 

29.000 

0 

394 

101,900 

22,000 

123,900 

Feb. 

2,579,000 

250.000 

107,000 

0 

316,000 

0 

400 

104,200 

43,800 

148,000 

Mar. 

2,818,000 

247.000         77,000 

7,000 

0 

4,000 

411 

109,000 

33,900 

142,900 

April 

2,940,000 

276,000 

110.000 

10,000 

0 

17,000 

412 

117,500 

46,600 

164,100 

May 

2,940,000 

282,000 

11,000 

12.000 

0 

0 

412 

124.200 

4,900 

129,100 

Jjne 

2,882,000 

297,000 

35,000 

14.000                 0 

0 

408 

125,400 

14,800 

140,200 

July 

2,755,000 

303,000 

43,000 

13.000 

0 

0 

402 

126,700 

17,900 

144,600 

Aug. 

2.604.000 

282.000 

44,000 

10,000 

0 

0 

394 

120,000 

18,800 

138,800 

Sept. 

2.469,000 

278,000 

121.000 

7.000 

0 

0 

388 

113,400 

49,200 

162.600 

Oct. 

2.,371,000 

264,000 

14.5,000 

5,000 

0 

0 

381 

110,300 

59,700 

170,000 

Nov. 

2,325,000 

271,000 

222.000 

0 

0 

0 

384 

109,400 

89,000 

198,400 

Dec. 
Total  or 

3,214,000 

1,238,000 

78,000 

1,228,000 

21,000 

398 

113,400 

42,900 

156,300 

average 

2.529,000 

239,000 

251,000 

0 

446,000 

0 

389 

97,400 

101,600 

199,000 

1901 

Jan. 

2,488,000 

227,000 

223,000 

0 

801.000 

0 

386 

101,900 

99,400 

201.300 

Feb. 

2,541,000 

251,000 

128,000 

0 

155,000 

0 

398 

104,200 

52,400 

156,600 

Mar. 

2.756,000 

249,000 

0 

7,000 

0 

0 

408 

109,000 

0 

109,000 

April 

2,882.000 

276,000 

67,000 

10,000 

0 

0 

412 

117,500 

28,500 

146,000 

May 

2,940.000 

282.000 

4,000 

12,000 

0 

0 

412 

124,200 

1,800 

126,000 

June 

2.882.000 

297,000 

34,000 

14,000 

0 

0 

408 

125,400 

14,200 

139,600 

July 

2,755,000 

303,000 

41.000 

13.000 

0 

0 

402 

126,700 

17,100 

143,800 

Aug. 

2,604,000 

282,000 

43.000 

10.000 

0 

0 

394 

120,000 

18,200 

138,200 

Sept. 

2,469,000 

278,000 

28.000 

7,000 

0 

0 

388 

113,400 

11,400 

124,800 

Oct. 

2,371,000 

265,000 

103.000 

5,000 

0 

0 

383 

110..300 

42,500 

152,800 

Nov. 

2,352,000 

272,000 

2.52,000 

0 

0 

0 

383 

109,400 

100,600 

210,000 

Dec. 
Total  or 

3,221,000 

1.174,000 

78,000 

1,402,000 

0 

397 

113,400 

40,400 

153,800 

average 

2.378.000 

240,000 

0 

0 

0 

0 

386 

97,400 

0 

97,400 

1902 

Jan. 

2,365,000 

230,000 

176.000 

0 

2,175,000 

0 

381 

101.900 

77,100 

179,000 

Feb. 

2,566,000 

251,000 

183,000 

0 

409,000 

0 

398 

104,200 

75,.300 

179,500 

Mar. 

2.8.38.000 

249,000 

187.000 

7,000 

0 

346,000 

408 

109,000 

81,500 

190,.500 

April 

2,940,000 

278.000 

210,000 

10.000 

0 

261,000 

409 

117,500 

91,400 

208,900 

May 

2,940,000 

282.000 

104.000 

12,000 

0 

7,000 

410 

124,200 

71,700 

195,900 

June 

2,882,000 

298.000 

69.000 

14,000 

0 

0 

406 

125,400 

29,000 

1.54,400 

July 

2.7.55,000 

304.000 

68,000 

13,000 

0 

0 

400 

126,700 

28,400 

1.55,100 

Aug. 

2.604,000 

282.000 

27.000 

10.000 

0 

0 

394 

120,000 

11.400 

131,400 

S.M)t. 

2.469,000 

278.000 

48.000 

7.000 

0 

0 

388 

113,400 

19,.500 

132,900 

Oct. 

2,371,000 

2.58.000 

190.000 

5,000 

0 

0 

336 

110,300 

81.100 

191,400 

Nov. 

2,747,000 

264,000 

241,000 

0 

352,000 

0 

400 

109,400 

100,600 

210.000 

Dec. 
Total  or 

3,211,000 

1,560,000 

78,000 

2,936,000 

614,000 

398 

113,400 

55,300 

168,700 

average 

2,6,52,000 

240,000 

264,000 

0 

772,000 

0 

388 

97,400 

106,900 

204,300 

1903 

Jan. 

2,489,000 

226,000 

222,000 

0 

120,000 

0 

390 

101,900 

100,100 

202,000 

Feb. 

2,518,000 

253,000 

242.000 

0 

580,000 

0 

394 

104.200 

99,600 

203,800 

Mar. 

2.812,000 

249,000 

225.000 

7,000 

46,000 

110,000 

408 

109,000 

98,100 

207,100 

April 

2,940,000 

276,000 

152.000 

10,000 

0 

20,000 

412 

117..500 

64.700 

182,200 

May 

2,940,000 

282,000 

42,000 

12,000 

0 

0 

412 

124,200 

18.300 

142,500 

June 

2,882,000 

297,000 

47,000 

14.000 

0 

0 

408 

12.5,400 

19.800 

145,200 

July 

2,755,000 

303,000 

39,000 

13.000 

0 

0 

402 

126,700 

16,.3O0 

143.000 

Aug. 

2,604,000 

282,000 

17,000 

10,003 

0 

0 

394 

120.000 

7,200 

127.200 

Sept. 

2.469,030 

278,000 

12.000 

7,000 

0 

0 

388 

113,400 

4.800 

118.200 

Oct. 

2.371,000 

261.000 :      156,000 

1         5,000 

0 

0 

390 

110,300 

65,600 

175.900 

Nov. 

2.873.000 

263,000 ;      229,000 

!            0 

310,000 

400 

109.400 

95.300 

204,700 

D.-c. 
Total  or 
average 

1  3,210.000'   1.647.000 

1 

78.000]   1.834,000 

1 

130,000 

399 

113,400 

57,800 

171,200 

'7'^'^. 


WATER    KKisOUKCES    OF    CALIFOIiNIA. 


TABLE  la  (Continued j.     KENNETT 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 
Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Esti- 
mated 

Without  flood  control 

Year  and 
month 

run-off 

Stage  of 

Power  draft 

Average  power  yield 

at 
dam 

reservoir 
at 

through  turbines  in 
acre-feet 

Evapora- 

Waste 
over 

Average 

in  kilowatts 
(Load  factor=( 

.75) 

site 

in 

acre-feet 

beginning 

tion  in 
acre-feet 

spillway 

in 
acre-feet 

power 

head  in 

feet 

of 
month  in 
acre-feet 

Primary 

Secondary 

•Primary 

Secondary 

Total 

1904 

Jan. 

473.000 

2,906,000 

229,000 

188,000 

0 

22,000 

412 

97.400 

80.000 

177,400 

Feb. 

1.742.000 

2,940.000 

217.000 

204,000 

0 

1,321,000 

410 

98.400 

92.400 

190,800 

Mar. 

2.877,000 

2,940,000 

248,000 

254.000 

0 

2,375,000 

403 

104.200 

105,800 

210,000 

April 

1,467.000 

2,940.000 

252,000 

235,000 

7,000 

973,000 

402 

109,000 

101.000 

210,000 

May 

914,000 

2.940,000 

279,000 

220,000 

10,000 

405.000 

406 

117,500 

92.500 

210.000 

June 

505,000 

2.940,000 

283.000 

196,000 

12,000 

48,000 

410 

124.200 

85,800 

210,000 

July 

377,000 

2,906,000 

298,000 

201,000 

14,000 

0 

40S 

125.400 

84,600 

210,000 

Aug. 

282,000 

2,770.000 

304,000 

131.000 

13.000 

0 

400 

126.700 

54,600 

181,300 

Sept. 

271,000 

2,604,000 

282,000 

114.000 

10,000 

0 

393 

120.000 

48,300 

168.300 

Oct. 

491,000 

2,469,000 

276,000 

201,000 

7,000 

0 

391 

11.3,400 

81,900 

195.300 

Nov. 

379,000 

2,476,000 

263,000 

241,000 

5,000 

0 

386 

110,300 

99,700 

210,000 

Dec. 

600,000 

2,346,000 

273,000 

2.52,000 

0 

0 

381 

109,400 

100,600 

210,000 

Total  or 
average 

10.378,000 

3,204,000 

2,437,000 

78,000 

5,144,000 

400 

113,000 

85,600 

198,600 

1905 

Jan. 

1,371,000 

2,421,000 

234,000 

87,000 

0 

531,000 

400 

97,400 

36,300 

133,700 

Feb. 

1,027,000 

2,940,000 

218,000 

231,000 

0 

578.000 

408 

101,900 

108,100 

210,000 

Mar. 

1,335,000 

2,940,000 

247.000 

252.000 

0 

836.000 

406 

104,200 

105,800 

210,000 

April 

753,000 

2,940,000 

250,000 

232,000 

7,000 

264.000 

407 

109,000 

101,000 

210,000 

May 

560,000 

2,940,000 

276.000 

207,000 

10,000 

67.000 

411 

117,500 

87,600 

205,100 

June 

365,000!  2,940,000 

283,000 

128,000 

12.000 

0 

410 

124,200 

56,100 

180,300 

July 

269,000 

2,882,000 

298,000 

84,000 

14,000 

0 

407 

125,400 

35,500 

160,900 

Aug. 

236,000 

2,755,000 

304,000 

70,000 

13,000 

0 

400 

126,700 

29,200 

1.55,900 

Sept. 

208,000 

2,604,000 

282.000 

51,000 

10,000 

0 

394 

120.009 

21,700 

141,700 

Oct. 

221,000 

2,469,000 

278,000 

34,000 

7,000 

0 

388 

113,400 

13.800 

127,200 

Nov. 

229,000 

2,371.000 

264,000 

53.000 

5,000 

0 

384 

110,300 

21,900 

132,200 

Dec. 
Total  or 
average 

249,000    2,278,000 

270,000 

0 

0 

0 

380 

109.400 

0 

109,400 

6.823,000 

3,204,000 

1,429.000 

78,000 

2.276.000 

400 

113,400 

51,000 

164.400 

1906 

Jan. 

851.000 

2,257,000 

237,000 

0 

0 

0 

393 

97,400 

0 

97,400 

Feb. 

872,000 

2,871,000 

217,000 

139.000 

0 

447,000 

409 

101,900 

64,700 

166,600 

Mar. 

1.646,000 

2,940,000 

247.000 

252.000 

0 

1.147.000 

406 

104,200 

105,800 

210,000 

April 

995.000 

2,940,000 

250,000 

233,000 

7.000 

505,000 

406 

109,000 

101,000 

210,000 

May 

817.000 

2.940.000 

278,000 

220,000 

10.000 

309.000 

408 

117,500 

92,.i00 

210,000 

June 

756.000 

2.940.000 

284.000 

196.000 

12.000 

265.000 

409 

124.200 

85,800 

210,000 

July 

362,000 

2,939.000 

297,000 

201.000 

14,000 

0 

408 

125.400 

84,600 

210,000 

Aug. 

280,000 

2.789,000 

304,000 

148,000 

13.000 

0 

400 

126,700 

61.700 

188,400 

Sept. 

247,000 

2,604,000 

283,000 

89,000 

10.000 

0 

394 

120,000 

37,800 

157,800 

Oct. 

251,000 

2  469  000 

278,000 

64,000 

7,000 

0 

388 

113,400 

26,100 

139,500 

Nov. 

256,000 

2.371,000 

265,000 

79,000 

5,000 

0 

383 

110,.300 

32.800 

143,100 

Dec. 
Total  or 
average 

648,000 

2,278,000 

272,000 

186.000 

0 

0 

382 

109,400 

74,300 

183,700 

7.981.000 

3,212.000 

1.807,000 

78,000 

2.673.000 

399 

113.400 

63,900 

177.300 

1907 
Jan. 

936,000 

2,468,000 

231.000 

44,000 

0 

189,000 

406 

97,400 

18,500 

115.900 

Feb. 

1 ,636,000 

2,940,000 

218,000 

231,000 

0 

1,187,000 

408 

101,900 

108,100 

210.000 

Mar. 

2,115,000 

2,940,000 

249,000 

254,000 

0 

1,612,000 

402 

104,200 

105,800 

210.000 

April 

1,250,000 

2,940,000 

251,000 

234,000 

7,000 

758,000 

404 

109,000 

101,000 

210.000 

May 

616,000 

2,940,000 

278,000 

219,000 

10,000 

139,000 

408 

117,500 

92,500 

210.000 

June 

421,000 

2,940.000 

232,000 

179.000 

12,000 

6.000 

410 

124,200 

78.200 

202.400 

July 

334.000:  2.882,000 

298,000 

149,000 

14,000 

0 

406 

125,400 

62,600 

188.000 

Aug. 

2',i  1,000    2,755,000 

301,000 

125,000 

13,000 

0 

400 

126,700 

52,000 

178,700 

Sept. 

252.()00|  2,601,000 

282,000 

95,000 

10,000 

0 

394 

120,000 

40,300 

160,300 

Oct. 

261,000    2.169,000 

278,000 

74,000 

7,000 

0 

388 

113.400 

30,100 

143,500 

Nov. 

256,000    2,371,000 

264,000 

80.000 

5,000 

0 

384 

110.300 

33,300 

143,600 

Dec. 
Total  or 
average 

479.000|  2.278.000 

273,000 

138,000 

0 

0 

380 

109.400 

55,100 

164,500 

8.877.000 

3,208,000 

1,822.000 

78.000 

3.891.000 

399 

113,400 

64,500 

177,900 

*Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


228 


RESERVOIR  ON  SACRAMENTO  RIVER. 

POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  1,  page  108.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.  F.  =  0.80 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maxim 

im  controlled  flow  at  Red  Bluff  125,000  sec.-ft.    Maximum  reservoir  space  required  454,000  ac.-ft. 

Stage  of 

Power  draft 

Average  power  yield 

Year  and 
month 

reservoir 

through  turbines  in 

Release 

Waste 

n  kilowatts 

at  ^ 

acre-feet 

Evapora- 

through 

over 

Average 

(Load  factor=0.75) 

beginning 

tion  in 
acre-feet 

flood 
control 

spillway 
in 

power 
head  in 

of 

month  in 

outletsin 

acre-feet 

feet 

acre-feet 

Primary 

Secondary 

acre-feet 

*Primary 

Secondary 

Total 

2,601.000 

238,000 

232,000 

0 

83,000 

0 

392 

97,400 

94,500 

191,900 

1904 

Jan. 

2,521,000 

236,000 

165,000 

0 

1,332,000 

0 

386 

98,400 

70,500 

168,900 

Feb. 

2,530,000 

256,000 

262,000 

0 

2,031,000 

0 

387 

104,200 

105,800 

210,000 

Mar. 

2,858,000 

250.000 

234,000 

7,000 

140,000 

748,000 

405 

109,000 

101,000 

210,000 

April 

2,940,000 

279.000 

220,000 

10,000 

0 

405,000 

406 

117,500 

92,500 

210,000 

May 

2,940,000 

283.000 

196.000 

12.000 

0 

48,000 

410 

124,200 

85,800 

210,000 

June 

2,906,000 

298,000 

201,000 

14.000 

0 

0 

406 

125,400 

84,600 

210,000 

July 

2,770,000 

304.000 

131,000 

13.000 

0 

0 

400 

126,700 

54,600 

181,300 

Aug. 

2,604,000 

282,000 

114.000 

10.000 

0 

0 

393 

120,000 

48,300 

168,300 

Sept. 

2,469,000 

276,000 

201,000 

7.000 

0 

0 

391 

113,400 

81,900 

195,300 

Oct. 

2,476,000 

263,000 

241,000 

5.000 

0 

0 

386 

110,300 

99.700 

210.000 

Nov. 

2,346,000 

273,000 

252,000 

0 

0 

0 

381 

109,400 

100,600 

210,000 

Dec. 
Total  or 
average 

3,238,000    2,449000 

78,000 

3,592,000 

1,201,000 

335 

113,000 

85,100 

198,100 

2,421,000 

238,000       179,000 

0 

743,000 

0 

391 

97,400 

72,600 

170,000 

1905 

Jan. 

2,632,000 

224,000 

229,000 

0 

607,000 

0 

393 

101,900 

103,600 

205,500 

Feb. 

2,599,030 

251,000 

238,000 

0 

524,000 

0 

398 

104,200 

98,400 

202.600 

Mar. 

2,921,000 

249,000 

231,000 

7,000 

29,000 

218,000 

408 

109,000 

101,000 

210,000 

April 

2,940,000 

276,000 

207,000 

10,000 

0 

67,000 

411 

117,500 

87,600 

205,100 

May 

2,940,000 

283,000 

128,000 

12,000 

0 

0 

410 

124,200 

56.100 

180,300 

June 

2,882,000 

298,000 

84,000 

14,000 

0 

0 

407 

125,400 

35,500 

160,900 

July 

2,755,000 

304,000 

70,000 

13,000 

0 

0 

400 

126,700 

29,200 

155,900 

Aug. 

2,604,000 

282,000 

51,000 

10,000 

0 

0 

394 

120,000 

21,700 

141,700 

Sept. 

2,469,000 

278,000 

34,000 

7,000 

0 

0 

388 

113,400 

13,800 

127,200 

Oct. 

2,371,000 

264,000 

53,000 

5,000 

0 

0 

384 

110,300 

21,900 

132,200 

Nov. 

2,278,000 

270,000 

0 

0 

0 

0 

380 

109,400 

0 

109,400 

Dec. 
Total  or 

3,217,000 

1,504,000 

78,000 

1,903,000 

285,000 

397 

113,400 

53,100 

166,500 

average 

2.257,000 

239,000 

52,000 

0 

109,000 

0 

390 

97,400 

21,600 

119,000 

1906 

Jan. 

2,708,000 

222,000 

141,000 

0 

611,000 

0 

398 

101,900 

63,700 

165,600 

Feb. 

2,606,000 

253,000 

241,000 

0 

924,000 

0 

394 

104,200 

98,900 

203,100 

Mar. 

2,834,000 

249,000 

232,000 

7,000 

1.36,000 

2i5,000 

408 

109,000 

101,000 

210,000 

April 

2,940,000 

278,000 

220,000 

10,000 

0 

309.000 

408 

117,500 

92,500 

210,000 

May 

2,940,000 

284,000 

196,000 

12,000 

0 

265,000 

409 

124,200 

85,800 

210,000 

June 

2,939,000 

297,000 

201,000 

14,000 

0 

0 

408 

125,400 

84,600 

210,000 

July 

2,789,000 

304,000 

148,000 

13,000 

0 

0 

400 

126,700 

61,700 

188,400 

Aug. 

2,604,000 

283,000 

89,000 

10,000 

0 

0 

394 

120,000 

37,800 

157,800 

Sept. 

2,469,000 

278,000 

64.000 

7,000 

0 

0 

388 

113,400 

26,100 

139,500 

Oct. 

2.371,000 

265,000 

79,000 

5,000 

0 

0 

383 

110,300 

32,800 

143,100 

Nov. 

2.278,000 

272,000 

•  186,000 

0 

0 

0 

382 

109,400 

74,300 

183,700 

Dec. 
Total  or 

3,224,000 

1,849,000 

78,000 

1,780,000 

839,000 

397 

113,400 

65,100 

178,500 

average 

2,468,000 

239,000 

247,000 

0 

430,000 

0 

389 

97,400 

100,300 

197,700 

1907 

Jan. 

2,488,000 

229,000 

243,000 

0 

1,122,000 

0 

384 

101,900 

•  108,100 

210,000 

Feb. 

2,530,000 

251,000 

259,000 

0 

1,314,000 

0 

392 

104,200 

105,800 

210,000 

Mar. 

2,818,000 

249,000 

234,000 

7,000 

178,000 

460,000 

406 

109,000 

101,000 

210,000 

April 

2,940,000 

278,000 

219,000 

10,000 

0 

139,000 

408 

117,500 

92,500 

210,000 

May 

2,940,000 

282,000 

179,000 

12,000 

0 

6,000 

410 

124,200 

78,200 

202,400 

June 

2,882,000 

298,000 

149,000 

14,000 

0 

0 

408 

125,400 

62,600 

188.000 

July 

2,755,000 

304,000 

125,000 

13,000 

0 

0 

400 

126,700 

52,000 

178.700 

Aug. 

2,604,000 

282,000 

95,000 

10,000 

0 

0 

394 

120,000 

40,300 

160,300 

Sept. 

2,469,000 

278,000 

74,000 

7,000 

0 

0 

388 

113,400 

30,100 

143.500 

Oct. 

2,371,000 

264,000 

80,000 

5,000 

0 

0 

384 

110,300 

33,300 

143,600 

Nov. 

2.278,000 

273,000 

138,000 

0 

0 

0 

380 

109,400 

55,100 

164.500 

Dec. 
Total  or 
average 

3,230,000 

2,042,000 

78,000 

3,044,000 

605,000 

395 

113,400 

71,400 

184,800 

224 


WATER   KESOUKCES   OF    t'ALIFOKNIA. 


TABLE  la  fContinued).     KENNETT 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 
WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 
(For  corresponding  yearly  sum 
Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Without  flood  control 

Esti- 

mated 

Year  and 
month 

run-o£f 

at 

dam 

site 

in 

acre-feet 

Stage  of 

Power  draft 

Average  power  yield 

reservoir 

throagh  turbines  in 

Waste 

Average 

n  kilowatts 

at 

acre 

-feet 

Evapora- 

over 

(I.oad  factor=0.75) 

beginning 

tion  in 
acre-feet 

spillway 

in 
acre-feet 

head  in 
feet 

of 
month  in 
acre-feet 

Primary 

Secondary 

•Primary 

Secondary 

Total 

1908 

Jan. 

904,000 

2,346,000 

234,000 

48,000 

0 

28,000 

400 

97,400 

20.200 

117,600 

Feb. 

970.000 

2,940,000 

217,000 

246,000 

0 

507,000 

409 

98,400 

111,600 

210,000 

Mar. 

669,000 

2,940.000 

246,000 

251,000 

0 

172,000 

408 

104,200 

105.800 

210.000 

April 

527,000 

2,940.000 

247,000 

225,000 

7,000 

48,000 

411 

109,090 

98,100 

207,100 

May 

492,000 

2,940,000 

276,000 

187,000 

10,000 

19,030 

411 

117,.500 

79.600 

197,100 

June 

,  .340.000 

2,940,000 

283,000 

103,000 

12,000 

0 

410 

124.200 

45,100 

169,.300 

July 

260,000 

2,882.000 

298,000 

75,000 

14,000 

0 

407 

125,400 

31,i'09 

157,000 

Aug. 

229,000 

2,755.000 

304,000 

63.000 

13,000 

0 

400 

126,700 

26.200 

152,900 

Sept. 

205,000 

2,604.000 

282.000 

48,000 

10,000 

0 

394 

120,000 

20,400 

140,400 

Oct. 

235,000 

2,409,000 

278,000 

48,000 

7,000 

0 

388 

113,400 

19.500 

132,900 

Nov. 

257,000 

2,371,000 

264.000 

81,000 

5,000 

0 

384 

110,,300 

33,800 

144,100 

Dec. 

267,000 

2,278,000 

273,000 

15,000 

0 

0 

380 

109,400 

5,900 

115,300 

Total  cr 

average 

5,.355,000 

3,202,000 

1,. 390,000 

78,000 

774,000 

400 

113,000 

49,500 

162,500 

1909 

Jan, 

3,260!000 

2,257,000 

236,000 

185,000 

0 

2,156,000 

396 

97,400 

76,200 

173.600 

Feb. 

2,526,000 

2,940.000 

221,000 

235,000 

0 

2,070,000 

400 

101,900 

108,100 

210,000 

Mar. 

977.000 

2.940,000 

248,000 

253,000 

0 

476.000 

404 

104,200 

105,800 

210,000 

April 

756,000 

2,940.000 

249.000 

231,000 

7,000 

209,030 

408 

109,000 

101,000 

210,000 

May 

.581,000 

2,940.000 

276,000 

216,000 

10,090 

79,000 

410 

117,500 

91,500 

209,000 

June 

410.000 

2,940,000 

282,000 

171,000 

12,000 

3,000 

410 

124.200 

74,900 

199.100 

July 

308,000 

2,882,000 

298,000 

123,000 

14,000 

0 

406 

125,400 

51.700 

177,100 

Aug. 

264,000 

2,755,000 

301,000 

98.000 

13,000 

0 

400 

126,700 

40,900 

167.600 

Sept. 

246,000 

2,601,000 

282,000 

89,000 

10,000 

0 

394 

120,000 

37.800 

157,800 

Oct. 

284,000 

2,469,000 

278.000 

97,000 

7,000 

0 

388 

113,400 

39,400 

152,800 

Nov. 

.538,000 

2,371,000 

264,000 

174,000 

5,000 

0 

384 

110,.300 

72,500 

182,800 

Dec. 
Total  or 

721,000 

2,406.000 

265,000 

244,000 

0 

0 

396 

109,400 

100,600 

210.000 

average 

10,871,000 

3,203,000 

2,116,000 

78,000 

5,053,000 

400 

113,400 

74,800 

188,200 

1910 

Jan. 

708.000 

2.678.000 

231.000 

69.000 

000 

146,000 

407 

97,400 

29,000 

126,400 

Feb. 

847,000 

2,940.000 

217,000 

230,000 

0 

400.000 

410 

101.900 

108.100 

210,000 

Mar. 

1,230.000 

2,940.000 

247.000 

251.000 

0 

741.000 

407 

104.200 

105.800 

210,000 

April 

605.000 

2.940,000 

249.000 

232  000 

7,000 

177.000 

408 

109.000 

101.000 

210,000 

May 

415,000 

2,940,000 

276.000 

128.000 

10.000 

1,000 

412 

117.,500 

54,400 

171,900 

June 

282.000 

2.940.000 

282.000 

46.000 

12,000 

0 

412 

124.200 

20,100 

144,.300 

July 

254,000 

2.882.000 

297,000 

70,000 

14,000 

0 

408 

125,400 

29,400 

151.800 

Aug. 

236.000 

2.7,55,000 

304,000 

70.000 

13,000 

0 

400 

126,700 

29.200 

155.900 

Sept. 

214.000 

2.601,000 

282.000 

57.000 

10,000 

0 

394 

120,000 

24.200 

114.200 

Oct. 

231,000 

2.469.000 

278.000 

41,000 

7,000 

0 

388 

113,400 

17.900 

131. .300 

Nov. 

274,000 

2.371.000 

265,000 

97,000 

5,000 

0 

383 

110,300 

40.300 

l.?0,600 

Dec. 
Total  or 
average 

436,000 

2.278.000 

273,000 

184,000 

0 

0 

380 

109,400 

73,400 

182,800 

5,801,000 

3,201,000 

1,478,000 

78,000 

1,465,000 

401 

113,400 

S2,300 

105,700 

1911 

Jan. 

700,000 

2,257,000 

240,000 

0 

0 

0 

385 

97,400 

0 

97,400 

Feb. 

848,000 

2,717,000 

217,000 

187,000 

0 

221,000 

409 

101,900 

88,100 

190,000 

Mar. 

1,278,000 

2,940,000 

246,000 

248,000 

0 

781,000 

408 

104,200 

104,400 

208,600 

April 

902,000 

2,940,000 

2.50.000 

232.000 

7,000 

473.000 

406 

109,000 

101.000 

210,000 

May 

671,000 

2.940.000 

278,000 

219,000 

10.000 

164.000 

408 

117..50O 

92,500 

210,000 

June 

431.000 

L'.'llll.lllMi 

282.000 

182.000 

12,000 

13,000 

410 

124,200 

79.600 

203,800 

July 

2H",000 

:'  ^\  J 11  ,(i 

:".IH,0I)0 

102.000 

14,000 

0 

400 

125,400 

42,900 

168,300 

Aug. 

211,000 

'  , : :,  MINI 

:f0l.000 

78.000 

13,000 

0 

400 

126,700 

32,.500 

15:1,200 

Sept 

2:!l.no!i 

:.'  Ml  1  iiiMi 

2.S2.000 

74,000 

10,000 

0 

394 

120,000 

30,700 

1.50,700 

Oct. 

210.000 

:;  ir,  1,1  II 111 

278.000 

59.000 

7.000 

0 

388 

113,400 

24,100 

137,.50O 

Nov. 

24Ul(tO 

j.:;ri,iiii'i 

264.000 

65,000 

5,000 

0 

384 

110.300 

26,900 

137,200 

Dec. 
Total  or 
average 

244.000 

2,278,(100 

273,000 

0 

0 

0 

380 

109,400 

0 

109,400 

6,383.000 

3.212.000 

1,446,000 

78,000 

1,655,000 

398 

113,400 

51..500 

164,000 

*Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE    CONTROL   OF    FLOODS   BY    RESERVOIRS. 


225 


RESERVOIR  ON  SACRAMENTO  RIVER. 

POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  1,  page  108.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.  F.  =  0.80 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft.    Maximum  reservoir  space  req 

Hired  451,000  ac.-ft. 

Stage  of 

Power  draft 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Average  power 

j'ield 

Year  and 

reservoir 

at 
beginning 

through  turbines  in 
acre-feet 

Evapora- 
tion in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Average 

power 

head  in 

feet 

in  kilowatt 
(Load  factor^ 

3.75) 

month 

of 
month  in 
acre-feet 

Primary 

Secondary 

'Primary 

Secondary 

Total 

1908 

2,346,000 

237,000 

94,000 

0 

264,000 

0 

394 

97.400 

38,300 

135,700 

Jan. 

2,655,000 

234,000 

210,000 

0 

629,000 

0 

388 

98,400 

90.800 

189,200 

Feb. 

2,552,000 

250.000 

88,000 

0 

37,000 

0 

401 

104,200 

36,300 

140,500 

Mar. 

2,846,000 

247,000 

134,000 

7,000 

0 

45.000 

411 

109,000 

58,300 

167,300 

April 

2,940,000 

276,000 

187,000 

10,000 

0 

19,000 

411 

117,500 

79,600 

197,100 

May 

2,940,000 

283,000 

103,000 

12,000 

0 

0 

410 

124,200 

45,100 

169,300 

June 

2,882,000 

298.000 

75,000 

14,000 

0 

0 

407 

125.400 

31,600 

157,000 

July 

2,755,000 

304,000 

63,000 

13,000 

0 

0 

400 

126,700 

26,200 

152,900 

Aug. 

2,604,000 

282,000 

48.000 

10,000 

0 

0 

394 

120,000 

20.400 

140,400 

S3pt. 

2.469,000 

278,000 

48,000 

7,000 

0 

0 

388 

113,400 

19,500 

132,900 

Oct. 

2,371,000 

264.000 

81,000 

5,000 

0 

0 

384 

110,300 

33,800 

144,100 

Nov. 

2,278,000 

273,000 

15.000 

0 

0 

0 

380 

109,400 

5,900 

115,303 

Dec. 
Total  or 

3,226,000 

1,146,000 

78,000 

930,000 

64,000 

398 

113,000 

40,200 

153,200 

average 

2,257,000 

242,000 

218,000 

0 

2,551,000 

0 

383 

97,400 

87,100 

181,590 

1909 

Jan. 

2,506,000 

227,000 

242,000 

0 

1,938,000 

0 

386 

101,900 

108,100 

210,000 

Feb. 

2,625,000 

249,000 

197,000 

0 

247,000 

0 

401 

104.200 

81,700 

185,900 

Mar. 

2,909,000 

249,000 

229.000 

7,000 

10,000 

230,000 

409 

109,000 

100.100 

209.100 

April 

2,940,000 

276.000 

216,000 

10,000 

0 

79,000 

410 

117,500 

91.500 

209,030 

May 

2,940,000 

282,030 

171,000 

12,000 

0 

3,000 

410 

124,200 

74,900 

199,100 

June 

2,882,000 

298,000 

123,000 

14,000 

0 

0 

406 

125,400 

51,700 

177,100 

July 

2,755,000 

304,000 

98,000 

13,000 

0 

0 

400 

126,700 

40,900 

167,600 

Aug. 

2,604,000 

282,000 

89,000 

10,000 

0 

0 

394 

120,000 

37,800 

157:800 

S?pt. 

2,469,000 

278,000 

97,000 

7.000 

0 

0 

388 

113,400 

39,400 

152,800 

Oct. 

2,371,000 

264,000 

174,000 

5,000 

0 

0 

384 

110,300 

72,500 

182,800 

Nov. 

2,466,000 

266,000 

245,000 

0 

39,000 

0 

395 

109,400 

103,600 

210,000 

Dec. 
Total  or 

3,217,000 

2,099,000 

78,000 

4,785,000 

312,000 

397 

113,400 

73,600 

187,000 

average 

2,637,000 

235,000 

139,000 

0 

327,000 

0 

398 

97,400 

57,000 

154,400 

1910 

.Tan. 

2,644,000 

221,000 

138,000 

0 

358,000 

0 

399 

101,900 

62.900 

164,800 

Feb 

2,774,000 

247,000 

239,000 

0 

351,000 

236,000 

406 

101,200 

100,400 

204.600 

Mar. 

2,940,000 

249,000 

232,000 

7,000 

0 

177,000 

408 

103,000 

101,000 

210.000 

April 

2,940,000 

276.000 

128,000 

10.000 

0 

1,000 

412 

117,500 

54,400 

171,900 

May 

2,940,000 

282,000 

40,000 

12,000 

0 

0 

412 

124.200 

20,100 

144,300 

Jun(3 

2,882,000 

297,000 

70,000 

14.000 

0 

0 

408 

125.400 

23,400 

154,800 

July 

2,755,000 

304,000 

70.000 

13,000 

0 

0 

400 

126,700 

23,200 

155,900 

Aug. 

2,604,000 

282,000 

57,000 

10,000 

0 

0 

3')4 

120,000 

24,200 

144,200 

S^pt. 

2,469,000 

278,000 

44,000 

7,000 

0 

0 

388 

113,400 

17,900 

131,300 

Oct. 

2,371,000 

265,000 

97.000 

5,000 

0 

0 

383 

110,300 

40,300 

150,600 

Nov. 

2,278,000 

274,000 

183,000 

0 

0 

0 

380 

103,400 

73,000 

182,400 

Dec. 
Total  or 

3,210,000 

1,443,000 

78,000 

1,036,000 

414,000 

399 

113,400 

50,800 

164,200 

average 

2,257,000 

241,000 

18,000 

0 

193,000 

0 

384 

97,400 

7.300 

104,700 

1911 

Jan. 

2,505,000 

226,000 

168.000 

0 

377,000 

0 

389 

101,900 

75,000 

176,900 

Feb. 

2,582,000 

253,000 

246.000 

0 

518.000 

0 

395 

104,200 

100,900 

205,100 

Mar. 

2,813,000 

249,000 

232,000 

7,000 

99,000 

248,000 

407 

109,000 

101,000 

210,000 

April 

2,940,000 

278.000 

219,000 

10,000 

0 

164,000 

408 

117,590 

92.500 

210,000 

May 

2,940,000 

282.000 

182,000 

12,000 

0 

13,000 

410 

124.200 

79,600 

203.800 

June 

2,882,000 

298,000 

102.000 

14.000 

0 

0 

406 

125,400 

42,900 

168,300 

July 

2,755,000 

304.000 

78.000 

13,000 

0 

0 

400 

126,700 

32,500 

159,200 

Aug. 

2.604,000 

282.000 

74,000 

10,000 

0 

0 

394 

120,000 

30,700 

150,700 

S3pt. 

2,469,000 

278,000 

59,000 

7,000 

0 

0 

388 

113,400 

24,100 

137,.i00 

Oct. 

2.371,000 

264,000 

65,000 

5,000 

0 

0 

384 

110,300 

26,900 

137,200 

Nov. 

2,278,000 

273,000 

0 

0 

0 

0 

380 

109,400 

0 

109,400 

Dec. 
Total  or 
average 

3,228,000 

1,443,000 

78,000 

1,217.000 

425,000 

396 

113,400 

50,800 

1 

164,200 

226 


WATER    RESOURCES   OF    CALIFORNIA. 


TABLE  la  (Continued).     KENNETT 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 
Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Esti- 
mated 

Without  flood  control 

Year  and 
month 

run -off 
at 
dam 

Stage  of 

Power  draft 

Average  power  yield 

reservoir 

through  turbines  in 

Waste 

Average 

in  kilowatts 

at 

acre 

feet 

Evapora- 

over 

(Load  factor=0.75) 

site 

in 

acre-feet 

beginning 

tion  in 
acre-feet 

spillway 

in 
acre-feet 

power 

head  in 

feet 

of  . 
month  in 
acre-feet 

Primary 

Secondary 

♦Primary 

Secondary 

Total 

1912 

Jan. 

517,000 

2.249,000 

239,000 

0 

0 

0 

388 

97,400 

0 

97.400 

Feb. 

396.000 

2,527,000 

221,000 

0 

0 

0 

399 

98,400 

0 

98,400 

Mar. 

635,000 

2,702,000 

246,000 

118,000 

0 

33,000 

409 

104,200 

50.300 

154,500 

April 

487,000 

2,940,000 

247,000 

182,000 

7,000 

51,000 

411 

109,030 

80,000 

189,000 

May 

714,000 

2,940,000 

277,000 

217.000 

10,000 

210,000 

410 

117,500 

91,900 

209.400 

June 

405,000 

2.940,000 

282.000 

158.000 

12,000 

11,000 

411 

124,200 

69.000 

193.200 

July 

274,000 

2,882.000 

268,000 

89.000 

14,000 

0 

406 

125,400 

37,500 

162.900 

Aug. 

238.000 

2.755.000 

304,000 

72.000 

13,000 

0 

400 

126,700 

30,000 

156.700 

Sept. 

242,000 

2.604,000 

282,000 

85.000 

10.000 

0 

394 

120,000 

36.000 

156.000 

Oct. 

226,000 

2.469,000 

278,000 

39,000 

7,000 

0 

388 

113,400 

15,900 

129.300 

Nov. 

432,000 

2.371.000 

264,000 

210,000 

5,000 

0 

385 

110,300 

87.100 

197,400 

Dec. 

369,000 

2,324,030 

273,000 

163,000 

0 

0 

380 

109,400 

64.500 

173,900 

Total  or 
average 

4.935,000 

3,211,000 

1.333,000 

78,000 

305,000 

398 

113,000 

46,900 

159,900 

1913 

Jan. 

763,000 

2,257,000 

237,000 

0 

0 

0 

392 

97.400 

0 

97,400 

Feb. 

387.000 

2,783,000 

216,000 

14,000 

0 

0 

411 

101,900 

6,400 

108.300 

Mar. 

441,000 

2.940,000 

243,000 

179,000 

0 

10,000 

413 

104,200 

76,200 

180,400 

April 

685,000 

2,940,000 

247,000 

231,000 

7,000 

200,000 

411 

109,000 

101,000 

210.000 

May 

521,000 

2,940,000 

276,000 

201,000 

10,000 

34,000 

411 

117,500 

85,500 

203,000 

June 

321,000 

2,940,000 

283,000 

84  000 

12.000 

0 

410 

124,200 

36,800 

161,000 

July 

263,000 

2.882,000 

298,000 

78,000 

14.000 

0 

407 

125,400 

32,800 

158,200 

Aug. 

2.32.000 

2,755,000 

304,000 

66.000 

13,000 

0 

400 

125,700 

27,600 

1M,300 

Sept. 

mo.ooo 

2,604,000 

282,000 

33,000 

10,000 

0 

394 

120,000 

14,000 

134,000 

Oct. 

202,000 

2,469,000 

278,000 

15,000 

7,000 

0 

388 

113,400 

6,000 

119,400 

Nov. 

316,000 

2,371,000 

265,000 

105,000 

5,000 

0 

383 

110,300 

43,600 

153,900 

Dec. 

696,000 

2,312,000 

272,000 

183,000 

0 

0 

381 

109,400 

72,900 

182,300 

Total  or 
average 

5,017,000 

3.201,000 

1,189,000 

78,000 

253,000 

400 

113.400 

42,100 

155,500 

1914 

Jan. 

2.797.000 

2.553,000 

233,000 

255,000 

0 

1,922,000 

401 

97.400 

105,500 

202,900 

Feb. 

1,359,000    2.940,000 

220,000 

234,000 

0 

905,000 

402 

101,900 

108,100 

210,000 

Mar. 

987,0001  2,940,000 

247,000 

252,000 

0 

488,000 

406 

104,200 

105,800 

210,000 

April 

1,137,000    2,940,000 

250,000 

232,000 

7,000 

648,000 

407 

109.000 

101,000 

210,000 

May 

703,0001  2.940,000 

278,000 

220,000 

10,000 

195,000 

408 

117,500 

92.500 

210.000 

June 

452,000 

2,940,000 

283.000 

196,000 

12.000 

13,000 

410 

124.200 

85,800 

210,000 

July 

309.000 

2,888,000 

298,000 

130,000 

14,000 

0 

406 

125,400 

54.800 

180,200 

Aug. 

248,000 

2,755,000 

304,000 

82,000 

13,000 

0 

400 

126,700 

34.100 

160,800 

Sept. 

225,000 

2,604,000 

282.000 

68,000 

10,000 

0 

394 

120  000 

28,800 

148,800 

Oct. 

269,000 

2.469,000 

278,000 

82,000 

7,000 

0 

388 

113.400 

33,200 

146.600 

Nov. 

252,000 

2,371,000 

265,000 

75.000 

5,000 

0 

383 

110,300 

31.100 

141.400 

Dec. 
Total  or 
average 

347.000 

2,278,000 

273.000 

95.000 

0 

0 

380 

109,400 

37.900 

147.300 

9.085.000 

3.211,000 

1.921.000 

78,000 

4,171,000 

399 

113,400 

68.000 

181.400 

1915 

Jan. 

895,000 

2,257.000 

237,000 

0 

0 

0 

394 

97,400 

0 

97,400 

Feb. 

2,298,000 

2,915,000 

221,000 

235,000 

0 

1,817,000 

400 

101,900 

108,100 

210,000 

Mar. 

1,264,000 

2,940,000 

248,000 

254,000 

0 

762,000 

403 

10».200 

105,800 

210,000 

April 

1,159.000 

2.940,000 

250,000 

233,000 

7.000 

669,000 

406 

109.000 

101.000 

210,000 

May 

1.256.000 

2.940,000 

279,000 

220,000 

10,000 

747,000 

406 

117.500 

92,500 

210,000 

June 

572,000 

2.940,000 

283,000 

195,000 

12,000 

99,000 

410 

124.200 

85,800 

210,000 

July 

343,000 

2,923.000 

298,000 

199.000 

14,000 

0 

406 

125.400 

83,900 

209,300 

Aug. 

266,000 

2.755,000 

3(M,000 

100,000 

13,000 

0 

400 

126.700 

41,700 

168,400 

Sept. 

215,000 

2,604.000 

282.000 

58.000 

10,000 

0 

394 

120,000 

2-1.7CO 

144,700 

Oct. 

233,000 

2.469,000 

278.000 

46.000 

7,000 

0 

388 

113,400 

18,700 

132,100 

Nov. 

251,000 

2,371,000 

264.000 

78.000 

fi,000 

0 

383 

110,303 

32,400 

142,700 

Dec. 
Total  or 
average 

699,000 

2,278,000 

270.030 

235.000 

0 

0 

387 

109,400 

94,900 

204,300 

9,454,000 

3.214.000 

1.853.000 

78,000 

4.094,000 

398 

113,400 

65,500 

178.900 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE    CONTROL    OF    FLOODS   BY    RESERVOIKS. 


227 


RESERVOIR  ON  SACRAMENTO  RIVER. 

POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  1,  page  108.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.  F.  =0.£0 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  U 

5,000  scc.-f  t.    Maximum  reservoir  space  req 

jired  454,000  ac.-ft. 

Stage  of 

Power  draft 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Ave 

rage  power  yield 

Vpur inn 

reservoir 

at 

through  turbines  in 
acre-feet 

Evapora- 

Waste 
over 

Average 

in  kilowatts 
(Load  factor=0.75) 

1  ttii  (iiiu 

month 

beginning 

tion  in 
acre-feet 

spillway 

in 
acre-feet 

power 

head  in 

feet 

of 
month  in 
acre-feet 

Primary 

Secondary 

*Primary 

Secondary 

Total 

1912 

2,249,000 

239,000 

0 

0 

0 

0 

388 

97,400 

0 

97,400 

Jan. 

2,527,000 

221,000 

0 

0 

0 

0 

399 

98,400 

0 

98,400 

Feb. 

2,702,000 

246,000 

118,000 

0 

0 

33,000 

403 

104,200 

50.300 

154,500 

Mar. 

2,940,000 

247,000 

182,000 

7,000 

0 

51,000 

411 

109,000 

80,000 

189,000 

April 

2,940,000 

277,000 

217,000 

10,000 

0 

210,000 

410 

117,.500 

91,900 

209,400 

May 

2,940,000 

282.000 

158,000 

12,000 

0 

11,000 

411 

124.200 

69,000 

193,200 

June 

2,882,000 

298,000 

89,000 

14,000 

0 

0 

406 

125,400 

37,500 

162,900 

July 

2,755,000 

301,000 

72,000 

13,000 

0 

0 

400 

126,700 

30,000 

156,700 

Aug. 

2,604,000 

282,000 

85,000 

10,000 

0 

0 

394 

120,000 

36,000 

156,000 

Sept. 

2,460,000 

278,000 

39,000 

7,000 

0 

0 

388 

113,400 

15,900 

129,300 

Oct. 

2,371,000 

264,000 

210,000 

5,000 

0 

0 

385 

110,300 

87,100 

197,400 

Nov. 

2,324,000 

273.000 

163,000 

0 

0 

0 

380 

109,400 

64,500 

173,900 

Dec. 
Total  or 
average 

3,211,000 

1,333,000 

78,000 

0 

305,000 

398 

113,000 

46,900 

159,900 

2,257,000 

240,000 

111,000 

0 

137,000 

0 

.386 

97,400 

45,000 

142,400 

1913 

Jan. 

2,532,000 

222,000 

17,000 

0 

0 

0 

399 

101,900 

7,600 

109,.500 

Feb. 

2,680,000 

247,000 

0 

0 

0 

0 

408 

104,200 

0 

104,200 

Mar. 

2,874,000 

249,000 

200,000 

7,000 

0 

163.000 

409 

109,000 

87,600 

196.600 

April 

2,940,000 

276,000 

201,000 

10,000 

0 

31,000 

411 

117,.500 

85,500 

203.000 

May 

2,940.000 

283,000 

84.000 

12,000 

0 

0 

410 

124,200 

36,800 

161,000 

June 

2,882,000 

298,000 

78,000 

li.OOO 

0 

0 

407 

125,400 

32,800 

1.58.200 

July 

2.755,000 

304.000 

66,000 

13.000 

0 

0 

400 

126,700 

27,600 

1.54,300 

Aug. 

2,604.000 

282,000 

33,000 

10,000 

0 

0 

394 

120,000 

14.000 

134,000 

Sept. 

2,460,000 

278,000 

15,000 

7,000 

0 

0 

388 

113,400 

6.000 

ll.t.400 

Oct. 

2,371,000 

265,000 

105,000 

5,000 

0 

0 

383 

110,300 

43,600 

1.53.900 

Nov. 

2,312,000 

272,000 

183,000 

0 

0 

0 

381 

109.400 

72.900 

182,300 

Dec. 
Total  or 
average 

3,216,000 

1,093,000 

78,000 

137.000 

197,000 

398 

113,400 

38.500 

151,900 

2,5.53.000 

2.38.000 

2,58.000 

0 

2,075,000 

0 

392 

97.400 

105,200 

202,600 

1914 

Jan. 

2,779,000 

224,000 

237.000 

0 

903,000 

0 

394 

101.900 

108,100 

210.000 

Feb. 

2,774,000 

249,000 

240,000 

0 

371.000 

0 

402 

101,200 

99,600 

203.800 

Mar. 

2,898,000 

249,000 

231,000 

7.000 

6,000 

602.000 

407 

109.000 

100.700 

209,700 

April 

2,940,000 

278,000 

220.000 

10.000 

0 

195,000 

408 

117..500 

92.500 

210.000 

May 

2,940,000 

283,000 

196.000 

12.000 

0 

13,000 

410 

124.200 

85,800 

210,000 

June 

2.888,000 

298.000 

13'^.000 

14.000 

0 

0 

406 

125,400 

54,800 

180,200 

July 

2,755,000 

304,000 

82.000 

13,000 

0 

0 

400 

126,700 

34.100 

160,800 

Aug. 

2,604,000 

282,000 

68,000 

10.000 

0 

0 

394 

120.000 

28,800 

148,800 

Sept. 

2,469,000 

278,000 

82  000 

7,000 

0 

0 

388 

113,400 

33,200 

146,600 

Oct. 

2.371.000 

265,000 

75,000 

5,000 

0 

0 

383 

110,300 

31,100 

141,400 

Nov. 

2.278,000 

273,000 

95,000 

0 

0 

0 

380 

109,400 

37,900 

147,300 

Dec. 
Total  or 
average 

3,221,000 

1.914,000 

78,000 

3,358,000 

810.000 

397 

113,400 

67,400 

180,800 

2.257,000 

239,000 

101,000 

0 

324,000 

0 

388 

97,400 

40,900 

138,.300 

1915 

Jan. 

2,488,000 

228,000 

242,000 

0 

1,625,000 

0 

386 

101,900 

108,100 

210,009 

Feb. 

2,691,000 

250,000 

256,000 

0 

522,000 

0 

399 

101,209 

105,801 

210,009 

Mar. 

2,927,000 

249,000 

234,000 

7,000 

38,000 

618,000 

405 

109,000 

101,009 

210,000 

April 

2,940,000 

279,000 

220,000 

10,000 

0 

747,000 

406 

117,590 

92,509 

210,000 

May 

2,940,000 

283,000 

195,000 

12,000 

0 

99,000 

410 

121,209 

85.800 

210,000 

June 

2,923,000 

298,000 

199,000 

14,000 

0 

0 

406 

125,400 

83,900 

209,300 

July 

2.755,000 

304,000 

100,000 

13  000 

0 

0 

400 

12(i,700 

41,709 

168,400 

Aug. 

2,004,000 

282,000 

58,000 

10,000 

0 

0 

394 

120,000 

24,700 

144,700 

Sept. 

2,469,000 

278,000 

46,000 

7,000 

0 

0 

388 

113,400 

18,709 

132,100 

Oct. 

2,371,000 

264,000 

78,000 

5,000 

0 

0 

384 

110.300 

32,400 

142,700 

Nov. 

2,278,000 

270,000 

235,000 

0 

0 

0 

387 

109,400 

94,909 

201.300 

Dec. 
Total  or 
average 

3,224,000 

1,964,000 

78,000 

2,599,000 

1,461,000 

396 

113,400 

69,009 

182,400 

228 


WATER   RESOURCES   OF   CALIFORNIA. 


TABLE  la  (Continued).     KENNETT 

WATER  AND  POWER  YIELD,  OPERATLNG  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 
Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Without  flood  control 

Esti- 

mated 

run-off 

at 

dam 

Year  and 
month 

Stage  of 

Power  draft 

Average  power  j-ield 

reservoir 
at 

through  turbines  in 
acre-feet 

Evapora- 

Waste 
over 

Average 

in  kilowatts 
(Load  factor=C 

.75) 

site 

in 

acre-feet 

beginning 

tion  in 
acre-feet 

spillway 

in 
acre-feet 

p>ower 

head  in 

feet 

of 
month  in 
acre-feet 

Primary 

Secondary 

*Primary 

Secondary 

Total 

1916 

Jan. 

1,166.000 

2,472,000 

232,000 

78,000 

0 

388,000 

403 

97,400 

32.700 

130,100 

Feb. 

1,616,000 

2,940,000 

219,000 

248,000 

0 

1,149.000 

406 

98.400 

111.600 

210,000 

Mar. 

1,215,000 

2,940,000 

248,000 

252,000 

0 

715,000 

404 

104,200 

10f,800 

210,000 

April 

678.000 

2.940,000 

251,000 

230,000 

7,000 

190,000 

408 

109,000 

100,300 

209,300 

May 

485,000 

2,940,000 

276,000 

173,000 

10,000 

26,000 

412 

117,500 

73,500 

191,000 

June 

353.000 

2,940,000 

283.000 

116,000 

12,000 

0 

410 

124.200 

50,800 

175.000 

July 

316.000 

2,882,000 

288,000 

131,000 

14,000 

0 

407 

125,400 

55,200 

180,600 

Aug. 

244,000 

2,755,000 

304,000 

78,000 

13.000 

0 

400 

126,700 

32,500 

159,200 

Sept. 

213,000 

2,604,000 

282,000 

56,000 

10,000 

0 

394 

120,000 

23,800 

143,800 

Oct. 

236.000 

2,469.000 

278,000 

49,000 

7,000 

0 

388 

113,400 

19,900 

133,300 

Nov. 

242,000 

2,371,000 

264,000 

66,000 

5,000 

0 

384 

110,300 

27,500 

137,800 

Dec. 

Tf»tj»l  nr 

363,000 

2,278,000 

273,000 

111,000 

0 

0 

380 

109,400 

44,500 

153,900 

1  utal  UL 

average 

7,127,000 

3,208,000 

1,588,000 

78,000 

2,468,000 

400 

113,000 

56,300 

169,000 

1917 

Jan. 

312.000 

2,257.000 

242,000 

0 

0 

0 

382 

97,400 

0 

97,400 

Feb. 

760,000 

2.327.000 

226,000 

0 

0 

0 

388 

101.900 

0 

101,900 

Mar. 

459,000 

2,861.000 

243,000 

126,000 

0 

11,000 

412 

104,200 

53,500 

157,700 

April 

906,000 

2,940,000 

248,000 

231,000 

7,000 

420,000 

410 

109.000 

101,000 

210,000 

May 

580,000 

2,940,000 

276,000 

210,000 

10.000 

84,000 

411 

1 17,500 

89,000 

206,500 

June 

329,000 

2.940,000 

283,000 

92.000 

12,000 

0 

410 

124,200 

40,300 

164,500 

July 

238  onn    2  882  cm 

297,000 

51,000 

14,000 

0 

402 

125,400 

22,700 

148,100 

Aug. 

214;( -:-'•'«• 

303,000 

•  49.000 

13,000 

0 

402 

126,700 

20,400 

147,100 

Sept. 

185.UI'"    _,■ ";  ■  "'- 

282,000 

28,000 

10,000 

0 

394 

120,000 

11,900 

131.900 

Oct. 

200,0UU,  j,l!j:<,u'j() 

278,000 

13,000 

7,000 

0 

388 

113,400 

5,400 

118.800 

Nov. 

224,000 

2,371,000 

264,000 

48,000 

5,000 

0 

384 

110,300 

20,000 

130.300 

Dec. 

298,000 

2,278,000 

273,000 

46,000 

0 

0 

380 

109,400 

18,400 

127,800 

Total  or 

average 

4,705,000 

3,215,000 

897,000 

78,000 

515,000 

397 

113,400 

32,000 

145,400 

1918 

Jan. 

249,000 

2,257,000 

243.000 

0 

0 

0 

380 

97,400 

0 

97,400 

Feb. 

399,000 

2,263,000 

229,000 

0 

0 

0 

383 

101,900 

0 

101,900 

Mar. 

772,000 

2,433,000 

251,000 

8,000 

0 

6,000 

398 

104,200 

3,400 

107,600 

April 

556,000 

2.940,000 

247.000 

208,000 

7.000 

94,000 

411 

109,000 

91,100 

200,100 

May 

314,000 

2,940,000 

276.000 

28,000 

10,000 

0 

412 

117.500 

12,000 

129.500 

Jane 

232.000 

2,940,000 

282,000 

0 

12,000 

0 

412 

124,200 

0 

124.200 

July 

200,000 

2,878.000 

297.000 

12,000 

14,000 

0 

408 

125,400 

5.100 

130.500 

Aug. 

192,000 

2,755.000 

303.000 

27,000 

13,000 

0 

402 

126,700 

11.200 

137,900 

Sept. 

180,000 

2,604,000 

282,000 

29.000 

10,000 

0 

394 

120,000 

12.400 

132,400 

Oct. 

258,000 

2,469,000 

278,000 

71.000 

7,000 

0 

388 

113,400 

28.900 

142.300 

Nov. 

246.000 

2,.37 1,000 

264,000 

70,000 

5,000 

0 

384 

1 10,300 

29.000 

139,300 

Dec. 
Total  or 

258,000 

2.278,000 

270,000 

9,000 

0 

0 

380 

109.400 

3.600 

113,000 

average 

3,862.000 

3.222,000 

462.000 

78.000 

100.000 

396 

113,400 

16.300 

129,700 

1919 

Jan. 

587,000 

2  257.000 

240,000 

0 

0 

0 

387 

97,400 

0 

97.400 

Feb. 

1,163.000 

2,604,000 

219.000 

150,000 

0 

458,000 

404 

101,900 

69.300 

171,200 

Mar. 

959.000 

2,940,000 

246.000 

251,000 

0 

462,000 

408 

104,200 

105.803 

210,000 

April 

752,000 

2,940.000 

249.000 

231.000 

7.000 

265,000 

408 

109,000 

101.000 

210,000 

May 

438,000 

2,940,000 

277,000 

151.000 

10,000 

0 

410 

1 17,500 

64,100 

181.600 

June 

252,000 

2,940,000 

282,000 

16.000 

12,000 

0 

412 

121,200 

7,100 

131,300 

July 

219,000 

2,882,000 

297,000 

35.000 

14.000 

0 

408 

125,400 

14.800 

140,200 

Aug. 

199,000 

2,755.000 

303,000 

34.000 

13.000 

0 

402 

126,700 

U.200 

140,900 

Sept. 

168.000 

2,604,000 

282,000 

11.000 

10,000 

0 

394 

120,000 

4,600 

124.600 

Oct. 

203.000 

2,469.000 

278,000 

16.000 

7,000 

0 

388 

113,400 

6,500 

1 19.900 

Nov. 

186,000 

2,,371.0OO 

264.000 

10.000 

5,000 

0 

384 

110,300 

4,200 

114,500 

Dec. 
Total  or 
average 

180,000 

2,278,000 

274,000 

0 

0 

0 

378 

109,400 

0 

109,400 

5,300,000 

3,211,000 

905,000 

78,000 

1,185,000 

399 

113.400 

32.400 

145,800 

*Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OP   FLOODS  BY   RESERVOIRS. 


229 


RESERVOIR  ON  SACRAMENTO  RIVER. 

POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  1,  page  108.) 


Installed  capacity  of  power  plant  400,000  k.v 

a.     P. 

F.=0.80 

Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  12 

5,000  sec.-ft.     Maximum  reservoir  space  required  454,000  ac.-ft. 

Stage  of 

Power  draft 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Average  power 

deld 

Year  and 
month 

reservoir 
at 

through  turbines  in 
acre-feet 

Evapora- 

Waste 
over 

Average 

in  kilowatts 
(Load  factor=( 

.75) 

beginning 

tion  in 
acre-feet 

spillway 

in 
acre-feet 

power 

head  in 

feet 

of 
month  in 
acre-feet 

Primary 

Secondary 

*Primary 

Secondary 

Total 

2.472,000 

240,000 

225,000 

0 

681,000 

0 

388 

97,400 

90,700 

188,100 

1916 

Jan. 

2,492,000 

237,000 

252,000 

0 

1,077,000 

0 

384 

98,403 

107,900 

203,300 

Feb. 

2,512.000 

252,000 

236,000 

0 

391,030 

0 

396 

104,230 

97,030 

201,200 

Mar. 

2,878,000 

219,000 

211,000 

7,000 

0 

149,000 

410 

103,030 

92,400 

201.400 

■April 

2,940,000 

276,000 

173,000 

10,000 

0 

26,000 

412 

117,500 

73.500 

191,030 

May 

2,940,000 

283,000 

116,000 

12,000 

0 

0 

410 

121.200 

53.800 

175,030 

Jane 

2,882,000 

298,000 

131,000 

14,000 

0 

0 

407 

125.400 

55.203 

183,600 

July 

2,755,000 

304.000 

78,000 

13,000 

0 

0 

400 

123.700 

32,530 

159,200 

Aug. 

2,604,000 

282.000 

53,000 

10.000 

0 

0 

394 

123,003 

23,830 

14.3,830 

Sept. 

2,469,000 

278.000 

49,000 

7.003 

0 

0 

388 

113.400 

19,903 

133,300 

Oct. 

2,371.000 

264,003 

66,000 

5,003 

0 

0 

384 

110,303 

27,500 

137,890 

Nov. 

2,278,000 

273,000 

111,000 

0 

0 

0 

380 

109,400 

44,500 

153,900 

Dec. 

Total  or 
average 

3,233,000 

1,704,000 

78,000 

2,149,000 

175,000 

396 

113,000 

59,500 

172,500 

2,257,000 

242,000 

0 

0 

0 

0 

382 

97,400 

0 

97,400 

1917 

Jan. 

2,327,000 

226,000 

26,000 

0 

178,000 

0 

387 

101,900 

11,600 

113,500 

Feb. 

2,657,000 

247,000 

8,000 

0 

0 

0 

408 

101.200 

3,500 

107,700 

Mar. 

2,861,000 

249,000 

196,000 

7,000 

0 

375,003 

408 

103,000 

85,600 

194,603 

April 

2,940,000 

276,000 

210,000 

10,000 

0 

84,000 

411 

117,533 

89,030 

206,503 

May 

2,940,000 

283,000 

92,000 

12,000 

0 

0 

410 

124,200 

40,300 

164.503 

June 

2,882.000 

297,000 

51,000 

14,000 

0 

0 

408 

125,400 

22,703 

148,100 

July 

2,755,000 

303,000 

49,000 

13,030 

0 

0 

402 

126,703 

23,400 

147,100 

-Aug. 

2,604,000 

282,000 

28.030 

10,000 

0 

0 

391 

120,000 

11,900 

131,930 

S?pt. 

2,469,000 

278,000 

13,000 

7,000 

0 

0 

388 

113.400 

5,400 

118,800 

Oct. 

2,371,000 

264,000 

48,000 

5,000 

0 

0 

381 

110,300 

20,003 

130,300 

Nov. 

2,278,000 

273,000 

46,000 

0 

0 

0 

380 

103,400 

18,403 

127,800 

Dec. 
Total  or 

3,220,000 

770,000 

78,000 

178,003 

459,000 

397 

113,400 

27,400 

*    140,800 

average 

2,257,000 

243,000 

0 

0 

0 

0 

380 

97,400 

0 

97.400 

1918 

Jan. 

2,263,000 

220.000 

0 

0 

0 

0 

383 

101,903 

0 

101,900 

Feb. 

2,433,000 

251,000 

8.000 

0 

0 

6,000 

398 

101,200 

3,400 

107,600 

Mar. 

2,940,000 

247,000 

208,030 

7,000 

0 

94,000 

411 

109,000 

91,100 

200,100 

.April 

2,940,000 

276,000 

28,003 

10,000 

0 

0 

412 

117,500 

12,000 

129,500 

May 

2,940.000 

288.000 

0 

12.030 

0 

0 

412 

124,200 

0 

124,200 

June 

2,878.000 

2,(7,000 

12,000 

14,000 

0 

0 

408 

125,400 

5,100 

130,500 

July 

2.755,000 

303,000 

27,000 

13,000 

0 

0 

402 

125,700 

11,200 

137,900 

Aug. 

2,604,000 

282,000 

29,000 

10.000 

0 

0 

394 

120,000 

12,400 

132,400 

Sept. 

2,469,000 

278,000 

71,000 

7,000 

0 

0 

388 

113,400 

28,900 

142,300 

Oct. 

2,371.000 

264.000 

70,000 

5,000 

0 

0 

381 

110.300 

29.000 

139.300 

Nov. 

2,278,000 

270.000 

9,000 

0 

0 

0 

380 

109,400 

3,600 

113,000 

Dec. 
Total  or 
average 

3,222,000 

462,000 

78,000 

0 

100,000 

396 

113,400 

16,300 

129,700 

2,257,000 

240,000 

71,000 

0 

34,000 

0 

385 

97,403 

23.000 

126,400 

1919 

Jan. 

2,499,0  }0 

226,000 

222,000 

0 

671,000 

0 

387 

101,900 

99,600 

201.500 

Feb. 

2,543,000 

251,000 

230,000 

0 

196,000 

0 

397 

104,200 

95,200 

199,400 

Mar. 

2,825.000 

249,000 

224.030 

7,000 

18,000 

139,000 

409 

109,000 

97.600 

206,600 

.\pril 

2,940,000 

277,000 

151,000 

10,000 

0 

0 

410 

117,500 

64,100 

181,600 

May 

2,940,000 

282,000 

16,000 

12,030 

0 

0 

412 

124,200 

7,100 

131.300 

June 

2,882,000 

297,000 

35,000 

14,000 

0 

0 

408 

125,400 

14,800 

140,200 

July 

2,755,000 

303.000 

34,000 

13.000 

0 

0 

402 

123,700 

14,200 

140.900 

Aug. 

2,604,000 

232,000 

11.000 

10,000 

0 

0 

394 

120,000 

4,600 

124,600 

Sept. 

2,469,000 

278,000 

16,000 

7,000 

0 

0 

388 

113,400 

6,500 

119,900 

Oct. 

2.371,000 

264,000 

10,000 

5,000 

0 

0 

381 

110,300 

4,200 

114,500 

Nov. 

2,278,000 

274,003 

0 

0 

0 

0 

378 

103,400 

0 

109,400 

Dec. 

Total  or 

average 

3,223,000 

1,020,000 

78.000 

919,000 

139,000 

396 

113,400 

36,000 

149,400 

230 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  la  (Continued).     KENNETT 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 
Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Without  flood  control 

Esti- 

mated 
run-off 

Year  and 
month 

Stage  of 

Power  draft 

Average  power 

yield 

at 
dam 

reservoir 

through  turbines  in 

Waste 

Average 

in  kilowatt 

3 

at 

acre-feet 

Evapora- 

over 

(Load  factor= 

3.75) 

site 

in 

acre-feet 

beginning 

tion  in 
acre-feet 

spillway 

in 
acre-feet 

power 

head  in 

feet 

of 
month  in 
acre-feet 

Primary 

Secondary 

♦Primary 

Secondary 

Total 

1920 

Jan. 

207,000 

2,184,000 

245,000 

0 

0 

0 

375 

97,400 

0 

97.400 

Feb. 

176,000 

2,146,000 

233,000 

0 

0 

0 

372 

98,400 

0 

98.400 

Mar. 

372,0001  2,089,000 

263.000 

0 

0 

0 

374 

104.200 

0 

104.200 

April 

493,000 

2,198,000 

262,000 

0 

6,000 

0 

383 

109,000 

0 

109,000 

May 

286,000 

2,423,000 

288,000 

0 

9.000 

0 

388 

117,500 

0 

117.500 

June 

216,000 

2,412.000 

296,000 

0 

10.000 

0 

386 

124,200 

0 

124,200 

July 

192,000 

2.32^,000 

312,000 

0 

12,000 

0 

380 

125,400 

0 

125.400 

Aug. 

176,000 

2.190,000 

321,000 

0 

11,000 

0 

372 

126,700 

0 

126.700 

Sept. 

140,000]  2,034,000 

301,000 

0 

8.000 

0 

363 

120,000 

0 

120.000 

Oct. 

180,000    1,865.000 

301,000 

0 

6,000 

0 

354 

113.400 

0 

113,400 

Nov. 

896,000!   1,738,000 

286,000 

25,000 

4,000 

0 

359 

110.300 

10.400 

120.700 

Dec. 
Total  or 
average 

1,121,000 

2,319,000 

265.000 

244,000 

0 

0 

397 

109,400 

100,600 

210,000 

4,455,000 

3,373,000 

269,000 

66.000 

0 

376 

113.000 

9.400 

122.400 

1921 
Jan. 

1,492,000 

2,931,000 

232,000 

270,000 

0 

981,000 

404 

97,400 

112.600 

210.000 

Feb. 

1.035,000 

2,940,000 

219,000 

232.000 

0 

584,000 

406 

101.900 

108.100 

210,000 

Mar. 

982,000 

2,940,000 

246,000 

252,000 

0 

484.000 

408 

101,200 

105,800 

210,000 

April 

559,000 

2,940,000 

247,000 

227,000 

7,000 

78,000 

410 

109,000 

99,000 

208,000 

May 

493,000 

2,940,000 

276,000 

195,000 

10,000 

12,000 

411 

117,500 

83.200 

200,700 

June 

316,000 

2,940,000 

283,000 

79,000 

12.000 

0 

410 

124,200 

34,600 

158.800 

July 

220,000 

2.882,000 

297,000 

36,000 

14,000 

0 

408 

125,400 

15,200 

140,600 

Aug. 

192,000 

2,755,000 

303,000 

27,000 

13,000 

0 

402 

126,700 

11.200 

13V.90O 

Sept. 

175,000 

2,604,000 

282,000 

18,000 

10,000 

0 

394 

120,000 

7,800 

127,800 

Oct. 

196,000 

2,469,000 

277,000 

0 

7,000 

0 

389 

113,400 

0 

113,400 

Nov. 

205,000 

2,381.000 

264,000 

39,000 

5,000 

0 

384 

110,300 

16,300 

126,600 

Dec. 
Total  or 
average 

390,000 

2,278,000 

273.000 

72,000 

0 

0 

381 

109,400 

28,900 

138,300 

6,255,000 

3,199,000 

1,447,000 

78,000 

2,139,000 

400 

113.400 

51,600 

165,000 

1922 

Jan. 

300,000 

2,323,000 

240,000 

0 

0 

0 

387 

97,400 

0 

97,400 

Feb. 

679,000 

2,383,000 

224,000 

0 

0 

0 

394 

101,900 

0 

101,900 

Mar. 

567,000 

2.8.38,000 

244,000 

142,000 

0 

79,000 

411 

104,200 

60.100 

164,300 

April 

604,000 

2,940,000 

248,000 

214,000 

7.000 

135,000 

410 

109,000 

93.600 

202,600 

May 

577,000 

2,940,000 

276,000 

209,000 

10.000 

82,000 

411 

117.500 

88,300 

205,800 

June 

317,000 

2,940,000 

283,000 

80,000 

12,000 

0 

410 

121.200 

35,000 

159,200 

July 

203,000 

2,882,000 

297.000 

19,000 

14,000 

0 

408 

125,400 

7,900 

133,300 

Aug. 

182,000 

2,755,000 

303.000 

17,000 

13,000 

0 

402 

126,700 

7,100 

1.33,800 

Sept. 

161,000 

2,604,000 

282  JWO 

4,000 

10,000 

0 

394 

120,000 

1,700 

121,700 

Oct. 

208,000 

2,469,000 

278,000 

21,000 

7,000 

0 

388 

113.400 

8.600 

122,000 

Nov. 

244,000 

2,371,000 

264,000 

68.000 

5.000 

0 

384 

110,300 

28,300 

138,600 

Dec. 

Total  or 
average 

462.000 

2,278,000 

273.000 

139,000 

0 

0 

380 

109,400 

55,100 

164.500 

4,504.000 

3,212.000 

913,000 

78.000 

296,000 

398 

113.400 

32,300 

145,700 

1923 

Jan. 

467,000 

2.328,000 

240,000 

130,000 

0 

0 

385 

97.400 

52,400 

149,800 

Feb. 

297,000 

2,425,000 

225,000 

0 

0 

0 

390 

101.900 

0 

101,900 

Mar. 

287,000 

2,497.000 

253.000 

0 

0 

0 

393 

104.200 

0 

104.200 

April 

632,000 

2..531,000 

250,000 

0 

7,000 

0 

405 

109,000 

0 

109,000 

May 

322,000 

2,906,000 

275,000 

3,000 

10.000 

0 

412 

117,500 

1,300 ! 

118.800 

June 

236,000    2,940,000 

282.000! 

0 

12.000 

0 

412 

124.200 

o; 

124.200 

July 

184,000;  2.882,000 

297,000 

0 

14,000 

0 

408 

125,400 

0 

125,400 

Aug. 

16.5,000    2,755,000 

303.000 

0 

13.000 

0 

402 

126.700! 

0 

126.700 

Sept. 

157,000    2,604,000 

282.000, 

0 

10.000 

0 

394 

120.000, 

0 

120,000 

Oct. 

187,000    2,469,000 

278,000 

0 

7.000 

0 

388 

113.4001 

0 

113,400 

Nov. 

176.000    2.371.000, 

264,000  i 

0 

5,000 

0 

384 

110,300 

0 

110,300 

Dec. 
Total  or 
average 

184.000    2,278,000 1 

274,000 

0 

0 

o; 

379 

109,400 

0 

109,400 

3,294.000. 

3,223,000 

133,000' 

78,000 1 

0 

398 

1 13.400  j 

4.600 

118,000 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OF   FLOODS   BY    RESERVOIRS. 


231 


RESERVOIR  ON  SACRAMENTO  RIVER. 

POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Dailj"  Basis. 

mary,  see  Table  1,  page  108.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.  F.  =0.80 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Blaff  125,000  sec.-f 

.     Maximum  reservoir  space  required  454,000  ac.-ft. 

Stage  of 

Power  draft 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Average  power  yield 

Year  and 
month 

reservoir 

at  _ 

through  turbines  in 
acre-feet 

Evapora- 

Waste 
over 

Average 

in  kilowatts 
(Load  factor=0 

.75) 

beginning 

tion  in 
acre-feet 

spillway 

in 
acre-feet 

power 

head  in 

feet 

of 
month  in 
acre-feet 

Primary 

Secondary 

"Primary 

Secondary 

Total 

2.184,000 

245,000 

0 

0 

0 

0 

375 

97,400 

0 

97,400 

1920 

Jan. 

2,146,000 

233,000 

0 

0 

0 

0 

372 

98,400 

0 

98.400 

Feb. 

2,089,000 

263,000 

0 

0 

0 

0 

374 

104,200 

0 

104,200 

Mar. 

2,198,000 

262,000 

0 

6,000 

0 

0 

383 

109,000 

0 

109,000 

April 

2,423,000 

288,000 

0 

9,000 

0 

0 

388 

117.500 

0 

117,500 

May 

2,412,000 

296,000 

0 

10,000 

0 

0 

386 

121,200 

0 

124,200 

June 

2,322.000 

312,000 

0 

12,000 

0 

0 

380 

125.400 

0 

125,400 

July 

2,190,000 

321,000 

0 

11,000 

0 

0 

372 

126,700 

0 

126.700 

Aug. 

2,034,000 

301,000 

0 

8,000 

0 

0 

363 

120,000 

0 

120,000 

Sept. 

1.865,000 

301.000 

0 

6.000 

0 

0 

354 

113,400 

0 

113,400 

Oct. 

1,738,000 

286,000 

25,000 

4,000 

0 

0 

359 

110.300 

10,400 

120,700 

Nov. 

2,319.000 

266,000 

245,000 

0 

202,000 

0 

395 

109,400 

100,600 

210,000 

Dec. 
Total  or 
average 

3,374,000 

270,000 

66,000 

202,000 

0 

375 

113,000 

9.400 

122,400 

2,727,000 

239.000 

277,000 

0 

1,050,000 

0 

390 

97,400 

112,600 

210,000 

1921 

Jan. 

2,653,000 

226,000 

240.000 

0 

660,000 

0 

390 

101,900 

108,100 

210,000 

Feb. 

2,562,000 

252,000 

244,000 

0 

226,000 

0 

336 

104,200 

100,900 

205,100 

Mar. 

2,822,000 

246,000 

164,000 

7,000 

0 

24,000 

411 

109,000 

71,900 

180,900 

April 

2,940,000 

276,000 

195,000 

10,000 

0 

12,000 

411 

117,500 

83,200 

200,700 

May 

2,940,000 

283,000 

79,000 

12.000 

0 

0 

410 

124,200 

34,600 

158,800 

June 

2,882,000 

297.000 

36000 

14.000 

0 

0 

408 

125,400 

1.5,200 

140,600 

July 

2.755,000 

303.000 

27,000 

13,000 

0 

0 

402 

126,700 

11,200 

137,900 

Aug. 

2,604.000 

282,000 

18,000 

10.000 

0 

0 

394 

120,000 

7,800 

127,800 

Sept. 

2,469,000 

277,000 

0 

7,000 

0 

0 

389 

113,400 

0 

113,400 

Oct. 

2,381,000 

264,000 

39.000 

5,000 

0 

0 

384 

110,300 

16.300 

120,600 

Nov. 

2,278,000 

273.000 

72,000 

0 

0 

0 

381 

109,400 

28,900 

138,300 

Dec. 
Total  or 
average 

3,218,000 

1,391,000 

78.000 

1,936,000 

36,000 

397 

113,400 

48,900 

162,300 

2,323,000 

240,000 

0 

0 

0 

0 

387 

97,400 

0 

97,400 

1922 

Jan. 

2,383,000 

225,000 

44.000 

0 

136,000 

0 

392 

101,900 

19,900 

121,890 

Feb. 

2,657,000 

246,000 

17,000 

0 

0 

21,000 

407 

104,200 

7,300 

111,500 

Mar. 

2,940,000 

248.000 

214,000 

7,000 

0 

135,000 

410 

109,000 

93,600 

202,600 

April 

2,940.000 

276.000 

209,000 

10,000 

0 

82,000 

411 

117,500 

88,300 

205,800 

May 

2,940,000 

283,000 

80.000 

12,000 

0 

0 

410 

124,200 

35,000 

159,200 

Jjne 

2,882.000 

297,000 

19,000 

14.000 

0 

0 

408 

125,400 

7,900 

133,300 

July 

2,755,000 

303,000 

17,000 

13,000 

0 

0 

402 

126,700 

7,100 

133,800 

Aug. 

2.004.000 

282,000 

4,000 

10,000 

0 

0 

394 

120,000 

1,700 

121,700 

Sept. 

2,469.000 

278,000 

21,090 

7,000 

0 

0 

388 

113,400 

8,600 

122,000 

Oct. 

2,371,000 

261,000 

68,000 

5,000 

0 

0 

384 

110,300 

28,300 

138,600 

Nov. 

2,278.000 

273,000 

139,000 

0 

0 

0 

380 

109,400 

55,100 

164,500 

Dec. 
Total  or 
average 

3,215,000 

832,000 

78,000 

136,000 

238,000 

398 

113,400 

29,400 

142,800 

2,328.000 

240.000 

130,000 

0 

0 

0 

385 

97,400 

52,400 

149,800 

1923 

Jan. 

2,425,000 

225.000 

0 

0 

0 

0 

390 

101,900 

0 

101,900 

Feb. 

2,497,000 

253,000 

0 

0 

0 

0 

393 

104,200 

0 

104,200 

Mar. 

2,531,000 

250,000 

0 

7,000 

0 

0 

405 

109,000 

0 

109,000 

April 

2,906.000 

275.000 

3,000 

10,000 

0 

0 

412 

117,500 

1,300 

118,800 

May 

2,940,000 

282,000 

0 

12,000 

0 

0 

412 

124.200 

0 

124,200 

June 

2,882,000 

297,000 

0 

14.000 

0 

0 

408 

125,400 

0 

125.400 

July 

2,755,000 

303,000 

0 

13,000 

0 

0 

402 

126.700 

0 

126,700 

Aug. 

2,604.000 

282,000 

0 

10,000 

0 

0 

394 

120,000 

0 

120,000 

Sept. 

2,469,000 

278,000 

0 

7,000 

0 

0 

388 

113,400 

0 

113.400 

Oct. 

2,371,000 

264,000 

0 

5,000 

0 

0 

384 

110,300 

0 

110,300 

Nov. 

2,278,000 

274,000 

0 

0 

0 

0 

379 

109.400 

0 

109,400 

Dec. 
Total  or 
average 

3,223,000 

133,000 

78,000 

0 

0 

398 

113,400 

4,600 

118,000 

232 


WATER   RESOURCES   OF   CALIFORNIA. 


TABLE  la  (Concluded).     KENNETT 

WATER  AND  POWER  YIELD.  OPERATING  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  correspH3nding  yearly  sum 
Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Without  flood  control 

Esti- 

mated 

1 

Year  and 
month 

run-off 

Stage  of 

Power  draft 

1           Average  power  yield 

at 
dam 

reservoir 

through  turbines  in 

Waste 

.Average 

1 

in  Idlowatt 

s 

at 

acre-feet 

Evapora- 

over 

(Load  factor=0.75) 

site 

in 

acre-feet 

beginning 

of 
month  in 
acre-feet 

tion  in 
acre-feet 

spillway 

in 
acre-feet 

power 

head  in 

feet 

Primary 

Secondary 

'Primary 

Sscondary 

Total 

1924 
Jan. 

203,000 

2,188,000 

245,000 

0 

0 

0 

376 

97,400 

0 

97,400 

Feb. 

332.000    2.146.000 

231,000 

0 

0 

0 

378 

98.400 

0 

98.400 

Mar. 

200,000;  2.247,000 

260.000 

0 

0 

0 

379 

104,200 

0 

104,200 

April 

176.000    2.187,000 

266,000 

0 

6,000 

0 

374 

109,000 

0 

109,000 

May 

155.000,  2.0;«.000 

301.000 

0 

8000 

0 

367 

117,500 

0 

117.500 

June 

141,0001   1.937.000 

315.000 

0 

9.000 

0 

358 

124.200 

0 

124,200 

July 

140.000    1.754,000 

341,000 

0 

10.000 

0 

345 

125.400 

0 

125,400 

Aug. 

140.000    1.543.000 

360,000 

0 

8,000 

0 

330 

126,700 

0 

126,700 

Sept. 

128.000    1.315,000 

349,000 

0 

6,000 

0 

312 

120.000 

0 

120.000 

Oct. 

178,000;  1,088.000 

363,000 

0 

4.000 

0 

293 

113.400 

0 

113,400 

Nov. 

317,0001      899,000 

356.000 

0 

2,000 

0 

282 

110,300 

0 

110.300 

Dec. 
Totol  or 
average 

321,000 1     858,000 

372,000 

0 

0 

0 

277 

109,400 

0 

109,400 

2,431,000 

3,759.000 

0 

53,000 

0 

339 

113,000 

0 

113.000 

1925 

Jan. 

301.000 

807,000      336,000 

0 

0 

0 

273 

97,400 

0 

97,400 

Feb. 

1,769,000 

772.000 

264,000 

0 

0 

0 

326 

101,900 

0 

101,900 

Mar. 

563,000 

2,277,000 

255,000 

0 

0 

0 

389 

104.200 

0 

104,200 

April 

926,000 

2,585,000 

250.000 

124.000 

7,000 

190,000 

403 

109,000 

53,800 

162.800 

May 

474.000 

2,940,000 

276,000 

167,000 

10,000 

21,000 

412 

117,.5O0 

70,800 

188,300 

June 

276,000 

2.940,000 

282,000 

40,000 

12,000 

0 

411 

124.200 

17,500 

141,700 

July 

173,000 

2,882,000 

297.000 

0 

14,000 

0 

408 

125,400 

0 

125.400 

Aug. 

167,000 

2.744,000 

304,000 

0 

13.000 

0 

400 

126,700 

0 

126,700 

Sept. 

163,000 

2.594.000 

282,000 

0 

10,000 

0 

394 

120,000 

0 

120.000 

Oct. 

181.000 

2,465,000 

278.000 

0 

7,000 

0 

388 

113,400 

0 

113,400 

Nov. 

192.000    2..%1,000       264,000 

6,000 

5.000 

0 

384 

110,300 

2,500 

112,800 

Dec. 
Total  or 
average 

235.000 

2.278,000       273,000 

0 

0 

0 

380 

100,400 

0 

109.400 

5,420,000 

3.361.000 

337,000 

78.000 

211,000 

381 

113.400 

12.100 

125,500 

Total  for 

30-year 

period. 

1896-1926 

188,012,000 

97,101,000 

37,953,000 

2,300,000 

50,674,000 

Average 
(or 

30-year 

period, 

1896-1926 

6,267,000 

3,236,000 

1,265,000 

77,000 

1,689,000 

395.8 

113,400 

44,800 

1 

158,200 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


233 


RESERVOIR  ON  SACRAMENTO  RIVER. 

POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


BY  RESERVOIR  OPERATING  DIAGRAM. 
tioRS  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  1,  page  108.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.  F.  =  0.80 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-f t.    Maximum  reservoir  space  required  451,000  ac.-ft. 

Stage  of 

Power  draft 

Release 

through 

flood 

control 
outletsin 
acre-feet 

Average  power 

(field 

Year  and 

reservoir 
at 

through  turbines  in 
acre-feet 

Evapora- 

Waste 
over 

Average 

in  kilowatts 
(Load  factor=:0.75) 

month 

beginning 

tion  in 

spillway 

head  in 
feet 

of 
month  in 
acre-feet 

Primary 

Sscondar)' 

acre-feet 

in 
acre-ftet 

*Primary 

Secondary 

Total 

1924 

2,188,000 

245,000 

0 

0 

0 

0 

376 

97,400 

0 

97,400 

Jan. 

2,146,000 

231,000 

0 

0 

0 

0 

378 

98,400 

0 

98.400 

Feb. 

2,247,000 

260.000 

0 

0 

0 

0 

379 

104,200 

0 

104,200 

Mar, 

2,187,000 

266,000 

0 

6,000 

0 

0 

374 

109,000 

0 

109,000 

April 

2,091,000 

301,000 

0 

8,000 

0 

0 

367 

117,500 

0 

117.500 

May 

1,937,000 

315,000 

0 

9,000 

0 

0 

358 

124,200 

0 

124.200 

June 

1,754,000 

341,000 

0 

10,000 

0 

0 

345 

125,400 

0 

125,400 

July 

1,543,000 

360,000 

0 

8,000 

0 

0 

330 

126,700 

0 

126,700 

Aug. 

1.315,000 

349,000 

0 

6,000 

0 

0 

312 

120,000 

0 

120,000 

Sept. 

1,088,000 

363,000 

0 

4,000 

0 

0 

293 

113,400 

0 

113.400 

Oct. 

899,000 

356,000 

0 

2,000 

0 

0 

282 

110,300 

0 

110,300 

Nov. 

858,000 

372,000 

0 

0 

0 

0 

277 

109,400 

0 

100,400 

Dec, 

Tntnl  nr 

3,759,000 

0 

53,000 

0 

0 

339 

113,000 

0 

113,000 

1  Ultll  KJl 

average 
1925 

807,000 

336,000 

0 

0 

0 

0 

273 

97,400 

0 

97,400 

Jan. 

772,000 

264,000 

0 

0 

0 

0 

326 

101,900 

0 

101.900 

Feb. 

2,277,000 

255,000 

0 

0 

0 

0 

389 

104,200 

0 

104.200 

Mar, 

2,585,000 

250.000 

124.000 

7,000 

0 

190.000 

403 

109.000 

53.800 

162,800 

April 

2,940.000 

276.000 

167.000 

10,000 

0 

21,000 

412 

117,500 

70,800 

188,300 

May 

2,940,000 

282.000 

40,000 

12.000 

0 

0 

411 

124,200 

17,500 

141,700 

June 

2,882,000 

297,000 

0 

14.000 

0 

0 

408 

125.400 

0 

125,400 

July 

2.744,000 

304.000 

0 

13.000 

0 

0 

400 

126,700 

0 

126,700 

Aug, 

2,594,000 

282.000 

0 

10.000 

0 

0 

394 

120,000 

0 

120,000 

Sept. 

2,465,000 

278.000 

0 

7.000 

0 

0 

388 

113,400 

0 

113,400 

Oct. 

2.361.000 

264.000 

6,000 

5,000 

0 

0 

384 

110,300 

2,500 

112,800 

Nov. 

2,278,000 

273,000 

0 

0 

0 

0 

380 

109,400 

0 

109,400 

Dec. 
Total  or 

3,361,000 

337,000 

78,000 

0 

211,000 

381 

113,400 

12,100 

125,500 

average 

Total  for 

30-year 

period, 

97,481,000 

37,094,000 

2,300,000 

40,414,000 

10,739,000 

1896-1926 

Average 
for 

30-year 
period. 

3,249,000 

1,236,000 

77,000 

1,347,000 

358,000 

393.8 

113,400 

43.400 

156,800 

1896-1926 

15— 52411 


2;i4 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  2a.     KENNETT  RESER 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet. 

Capacity  of  reservoir  2,940,000  acre-feet. 


Estimated 

Without  flood  control 

Irrigation 

Year  and 
month 

run-off 
at  dam 
site  in 

Stage  of 
reservoir 

at 

draft  in 

acre-feet 

(no 

Evapora- 

Power 

draft 

through 

turbines 

Waste 
over 

Deficiency 

in 

irrigation 

supply 

Average 
power 
head 

Average 
power 
yield  in 

acre-feet 

beginning 

deduction 

tion  in 

spillway 

through 

kilowatts 

of 

for  down- 

acre-feet 

in 

period  of 

(Load 

month  in 
acre-feet 

stream 
prior 
rights) 

in 
acre-feet 

acre-feet 

in 
a(!re-feet 

operation 
in  feet 

factor= 
1.00) 

1896 

Jan. 

1,980,000 

1,860,000 

0 

0 

216,000 

684,000 

0 

400 

89,900 

Feb. 

474.000 

2,940,000 

0 

0 

439,000 

35,000 

0 

411 

199,400 

Mar. 

738.000 

2,940,000 

43,000 

0 

5:2,000 

206,000 

0 

410 

225,300 

April 

891,000 

2,940,000 

214,000 

7,000 

631,000 

253.000 

0 

408 

275,800 

May 

1,194,000 

2,940,000 

684,000 

10,000 

663,000 

£00,000 

0 

406 

280,000 

June 

536,000 

2,940,000 

855,000 

12,000 

648,000 

0 

0 

339 

280,000 

July 

313,000 

2,609,000 

941,000 

13,000 

704,000 

0 

0 

376 

280,000 

Aug. 

268,000 

1,968,000 

855,000 

10.000 

769,000 

0 

0 

340 

280.000 

Sept. 

2.58.000 

1,371,000 

513,000 

6,000 

513.000 

0 

0 

312 

176.100 

Oct. 

262.000 

1,110,000 

171,000 

4,000 

171,000 

0 

0 

309 

56,200 

Nov. 

472,000 

1,197,000 

0 

3,000 

0 

0 

0 

0 

Dec. 

920.000 

1,666,000 

0 

0 

0 

0 

0 

0 

Total  or 
average 

8,306,000 

4,276,000 

65,000 

5.286,000 

1,678,000 

0 

375 

178,400 

1897 

Jan. 

577,000 

2,586,000 

0 

0 

141,000 

82,000 

0 

411 

59,800 

Feb. 

1,338,000 

2,940,000 

0 

0 

599,000 

739,000 

0 

406 

280.000 

Mar. 

737,000 

2,940,000 

43,000 

0 

601,000 

136,000 

0 

409 

254,600 

April 

858,000 

2,940,000 

214,000 

7,000 

63;),000 

212,000 

0 

408 

280,000 

May 

5.54,000 

2,940,000 

684,000 

10,000 

660,000 

3,000 

0 

408 

280,000 

June 

310.000 

2,797,000 

8.')5,000 

11,000 

663,000 

0 

0 

389 

280,000 

July 

275,000 

2,241,000 

911,000 

12.000 

741  000 

0 

0 

354 

280,000 

Aug. 

254,000 

1,563,000 

855,000 

9,000 

803.000 

0 

0 

309 

264.400 

Sept. 

247,000 

953,000 

513,000 

5,000 

513,000 

0 

0 

272 

152,400 

Oct. 

262,000 

682,000 

171,000 

3.000 

171,000 

0 

.     0 

266 

48,000 

Nov. 

274,000 

770,000 

0 

2,000 

0 

0 

0 

0 

Dec. 

366,000 

1,042,000 

0 

0 

0 

0 

0 

0 

Total  or 
average 

6,052,000 

4,276,000 

59,000 

5,531,000 

1,172,000 

0 

359 

180,800 

1998 

Jan. 

257.000 

1,408,000 

0 

0 

0 

0 

0 

0 

Feb. 

478.000 

1,665,000 

0 

0 

0 

0 

0 

0 

Mar. 

380.000 

2,143,000 

43,000 

0 

43,000 

0 

0 

385 

17,300 

April 

274.000 

2,480,000 

214,000 

7,000 

211,000 

0 

0 

395 

91,000 

May 

300,(X)0 

2,533,000 

684.000 

9,000 

081,000 

0 

0 

383 

275,000 

June 

304,000 

2,140,000 

855,000 

10,000 

717,000 

0 

0 

353 

280,000 

July 

237,000 

1,579,000 

941.000 

9,000 

800,000 

0 

0 

306 

260.200 

Aug. 

225,000 

866,000 

855,000 

6,000 

091,000' 

0 

0 

229 

162.000 

Sept. 

198,000 

230.000 

426.000 

2,000 

0 

0 

87,000 

0 

Oct. 

221,000 

0 

171,000 

0 

0 

0 

0 

0 

Nov. 

217,000 

50.000 

0 

0 

0 

0 

0 

0 

Dec. 

217,000 

267.000 

0 

0 

0 

0 

0 

0 

ToUl  or 
average 

3,308,000 

4,189.000 

43,000 

3,149,000 

0 

87,000 

342 

91,200 

1899 

Jan. 

605.000 

484,000 

0 

0 

0 

0 

0 

0 

Feb. 

253,000 

1.089,000 

0 

0 

0 

0 

0 

0 

Mar. 

900,000 

1,342,000 

43,000 

0 

43,000 

0 

0 

347 

15,900 

April 

456,000 

2,199,000 

214,000 

6,030 

214,000 

0 

0 

384 

89.300 

May 

330,000 

2.435.000 

684,000 

9,000 

684,000 

0 

0 

379 

272,400 

June 

302,000 

2.072.000 

K  ■  ■.  nnr  1 

0,000 

726,000 

0 

0 

348 

280,000 

July 

21(1.00(1 

1,.'.  1(1.0(1(1 

9,000 

790,000 

0 

0 

300 

252,000 

Aug. 

221.(1(1(1 

NOO  (lOII 

5,000 

673,000 

0 

0 

217 

146,100 

Sept. 

197.0(10 

Hi  1.01 10 

1,000 

0 

0 

153.000 

0 

Oct. 

252.000 

0 

171,000 

0 

0 

0 

0 

0 

Nov. 

645,000 

81,000 

0 

0 

0 

0 

0 

0 

Dec. 
ToUl  or 
average 

646,000 

726.000 

0 

0 

0 

0 

0 

0 

5.050.000 

4,123,000 

39,000 

3,130,000 

0 

153,000 

329 

88.700 

THE   CONTROL   OF   FLOODS   BY    RESERVOIRS. 

VOIR  ON  SACRAMENTO  RIVER. 

IRRIGATION  WITH  INCIDENTAL  POWER  GENERATION 


BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  2,  page  1 10.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 

Installed  capacity  of  power  plant  400,000  k.v.a.     P.P.  =  0.80. 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft.    M 

xximum  reservoir  space  required  454,000  ac.-ft. 

Irrigation 

Stage  of 
reservoir 

draft  in 
acre-feet 

Power 

draft 

through 

turbines 

Release 
through 
flood 
control 
outlets  in 
acr  e-feet 

Waste 

Deficiency 

Average 
power 

Average 
power 

Year  and 

at 

beginning 

of 

Cno 
dednction 
for  down- 

Evapora- 
tion in 
acre-feet 

over 

spillway 

in 

in 

irrigation 
supply 

head 
through 
period  of 

yield  in 

lulowatts 

(Load 

month 

month  in 
acre-feet 

stream 
prior 

in 
acre-feet 

acre-feet 

in 
acre-feet 

operation 
in  feet 

factor= 
1.00) 

rights) 

1896 

1.860,000 

0 

0 

246,000 

1,085,000 

0 

0 

382 

99.100 

Jan. 

2.509,000 

0 

0 

235,000 

29,000 

0 

0 

398 

104.000 

Feb. 

2,719,000 

43,000 

0 

321.000 

34,000 

162,000 

0 

407 

134,900 

Mar. 

2,940,000 

214,000 

7.000 

631,000 

0 

253,000 

0 

408 

275.800 

April 

2.940,000 

684,000 

10,000 

663.000 

0 

500,000 

0 

406 

280,000 

May 

2,940,000 

855,000 

12,000 

648.000 

0 

0 

0 

399 

280,000 

June 

2,609,000 

941,000 

13,000 

704,000 

0 

0 

0 

376 

280,000 

July 

1,968.000 

855.000 

10,000 

769.000 

0 

0 

0 

340 

280,000 

Aug. 

1,371,000 

513,000 

6,000 

513,000 

0 

0 

0 

312 

176,100 

Sept. 

1,110,000 

171,000 

4,000 

171,000 

0 

0 

0 

309 

56,200 

Oct. 

1,197,000 

0 

3,000 

0 

0 

0 

0 

0 

Nov. 

1,666,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

4,276,000 

65,000 

4,901,000 

1,148,000 

915,000 

0 

373 

164,000 

1897 

2,586,000 

0 

0 

477,000 

178,000 

0 

0 

392 

195,700 

Jan. 

2,508,000 

0 

0 

618,000 

698,000 

0 

0 

385 

276,000 

Feb. 

2,530,000 

43,000 

0 

416,000 

40,000 

0 

0 

3J8 

171,600 

Mar. 

2.811,000 

214,000 

7,000 

5.54,000 

0 

168.000 

0 

408 

242,100 

April 

2,940,000 

684.000 

10,000 

660.000 

0 

3,000 

0 

408 

280,000 

May 

2.797,000 

855.000 

11,000 

663,000 

0 

0 

0 

389 

280,000 

June 

2,241,000 

941.000 

12,000 

741,000 

0 

0 

0 

354 

280,000 

July 

1,563,000 

855,000 

9,000 

803,000 

0 

0 

0 

309 

264,400 

Aug. 

953,000 

513,000 

5,000 

513,000 

0 

0 

0 

272 

152,400 

Sept. 

682,000 

171.000 

3,000 

171,000 

0 

0 

0 

266 

48,000 

Oct. 

770,000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

1,042,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

4,276.000 

59,000 

5,616,000 

916,000 

171,000 

0 

358 

181,900 

1898 

1,408,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

1,665,000 

0 

0 

0 

0 

0 

0 

0 

Feb. 

2,143,000 

43,000 

0 

43,000 

0 

0 

0 

385 

17,300 

Mar. 

2.480,000 

214,000 

7,000 

214,000 

0 

0 

0 

395 

91,000 

April 

2,533,000 

084,000 

9,000 

684,000 

0 

0 

0 

383 

275,000 

May 

2,140,000 

855,000 

10,000 

717,000 

0 

0 

0 

353 

280,000 

June 

1,579,000 

941,000 

9.000 

800,000 

0 

0 

0 

306 

260,200 

July 

866,000 

855,000 

6,000 

691,000 

0 

0 

0 

229 

162,000 

Aug. 

230,000 

426,000 

2,000 

0 

0 

0 

87,000 

0 

Sept. 

0 

171,000 

0 

0 

0 

0 

0 

0 

Oct. 

50,000 

0 

0 

0 

0 

0 

0 

0 

Nov. 

267,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,189,000 

43,000 

3,149,000 

0 

0 

87,000 

342 

91,200 

1899 

484,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

1,089,000 

0 

0 

0 

0 

0 

0 

0 

Feb. 

1,342,000 

43,000 

0 

43,000 

0 

0 

0 

347 

15,900 

Mar. 

2,199,000 

214,000 

6,000 

214,000 

0 

0 

0 

384 

89,300 

April 

2,435,000 

684,000 

9,000 

684,000 

0 

0 

0 

379 

272,400 

May 

2,072,000 

855,000 

9,000 

726,000 

0 

0 

0 

348 

280,000 

June 

1,510,000 

941,000 

9,000 

790,000 

0 

0 

0 

300 

252,000 

July 

800,000 

855,000 

5,000 

673.000 

0 

0 

0 

217 

146,100 

Aug. 

164,000 

360.000 

1,000 

0 

0 

0 

153,000 

0 

Sept. 

0 

171,000 

0 

0 

0 

0 

0 

0 

Oct. 

81,000 

0 

0 

0 

0 

0 

0 

0 

Nov. 

726,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,123,000 

39,000 

3,130,000 

0 

0 

153,000 

329 

88,700 

236 


WATER  RESOURCES  OF  CALITORNIA. 


TABLE  2a  (Continued!.     KENNETT 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet. 

Capacity  of  reservoir  2,940,000  acre-feet. 


Estimated 

Without  flood  control 

Irrigation 

Year  and 
month 

run-off 
at  dam 

Stage  of 
reservoir 

draft  in 
acre-feet 

Power 

draft 

through 

turbines 

Waste 

Deficiency 

Average 
power 

.\verage 
power 

site  in  ■ 

at 

(no 

Evapora- 

over 

in 

irrigation 

supply 

head 

yield  in 

acre-feet 

bsginning 

deduction 

tion  in 

spillway 

through 

kilowatts 

of 

for  down- 

acre-feet 

in 

period  of 

(T,na(l 

month  in 
acre-feet 

stream 
prior 
righls) 

in 
acre-feet 

acre-feet 

in 
acre-feet 

operation 
in  feet 

factors 
1.00) 

1900 

Jan. 

1,299.000 

1,372,000 

0 

0 

0 

0 

0 

0 

Feb. 

391.000 

2,671,000 

0 

0 

122,000 

0 

0 

4ii 

57.300 

Mar. 

912.000 

2,940.000 

43,000 

0 

585,000 

327,000 

0 

409 

247,400 

April 

457,000 

2,940.000 

214.000 

7,000 

450,000 

0 

0 

412 

197,800 

May 

413.000 

2.940,000 

684.000 

10,000 

666.000 

0 

0 

404 

280,000 

June 

247,000 

2,659,000 

855,000 

11,000 

675,000 

0 

0 

380 

280,000 

July 

219.000 

2,010.000 

941,000 

11.000 

769,000 

0 

0 

339 

280,000 

Aug. 

208.000 

1,307,000 

855,000 

8,000 

772,000 

0 

0 

284 

232.500 

Sept. 

201.000 

652,000 

513,000 

4.000 

513,000 

0 

0 

230 

124.400 

Oct. 

308,000 

336,000 

171,000 

2,000 

171,000 

0 

0 

222 

38,200 

Nov. 

368,000 

471,000 

0 

2.000 

0 

0 

0 

0 

Dec. 
Total  or 
average 

697,000 

837,000 

0 

0 

0 

0 

0 

0 

5.720,000 

4,276.000 

55,000 

4.723,000 

327,000 

0 

337 

145,500 

1901 
Jan. 

895,000 

1,534.000 

0 

0 

0 

0 

0 

0 

Feb. 

1.304,000 

2.429,000 

0 

0 

195.000 

598,000 

0 

400 

89.700 

Mar. 

749,000 

2,940.000 

43,000 

0 

588,000 

161,000 

0 

409 

348,800 

April 

382,000 

2.940,000 

214,000 

7,000 

3/5,000 

0 

0 

412 

165,000 

May 

411,000 

2.940,000 

684.000 

10,000 

663,000 

0 

0 

404 

280.000 

June 

240,000 

2,657,000 

855.000 

11,000 

675.000 

0 

0 

380 

280,000 

July 

218,000 

2,031,000 

941,000 

11,000 

772.000 

0 

0 

339 

280,000 

Aug. 

206,000 

1,297,000 

855,000 

.    8,000 

769,000 

0 

0 

283 

230,900 

Sept. 

200,000 

640,000 

513,000 

4.000 

513,000 

0 

0 

228 

123.100 

Oct. 

215,000 

323.000 

171.000 

2,000 

171,000 

0 

0 

211 

35,900 

Nov. 

354.000 

365,000 

0 

1,000 

0 

0 

0 

0 

Dec. 
Total  or 
6  V --rage 

550,000 

718.000 

0 

0 

0 

0 

0 

0 

5.724,000 

4.276,000 

54.000 

4.721.000 

759.000 

0 

336 

144,900 

1902 

Jan. 

227,000 

1.268,000 

0 

0 

0 

0 

0 

0 

Feb. 

2,782,000 

1,495.000 

0 

0 

240.000 

1,097,000 

0 

398 

110,100 

Mar. 

1,115,000 

2,940,000 

43.000 

0 

648.000 

467.000 

0 

407 

273,700 

April 

891,000 

2.940,000 

214,000 

7,000 

634.000 

250,000 

0 

408 

277.200 

May 

765,000 

2.940,000 

684,000 

10,000 

660.000 

105,000 

0 

409 

280,000 

June 

407,000 

2.906.0O0 

855,000 

12,000 

654.000 

0 

0 

397 

280,000 

July 

254,000 

2,446,000 

941,000 

13,000 

719.000 

0 

0 

366 

280,000 

Aug. 

231.000 

1,746.000 

855,000 

9.000 

812.000 

0 

0 

323 

280,000 

Sept. 

184,000 

1,116.000 

513,000 

5,000 

513.000 

0 

0 

285 

160.600 

Oct. 

235,000 

782,000 

171,000 

3.000 

171,000 

0 

0 

276 

50,000 

Nov. 

829.000 

843,000 

0 

2.000 

0 

0 

0 

0 

Dec. 
Total  or 
average 

762,000 

1,670,000 

0 

0 

0 

0 

0 

0 

8.685,000 

4.276.000 

61.000 

5,051.000 

1,919,000 

0 

361 

166,300 

1903 

Jan. 

l.ll.'i.OOO 

2.432.000 

0 

0 

151.000 

454,000 

0 

401 

63.000 

Feb. 

633.000 

2.940.000 

0 

0 

565,000 

68.000 

0 

410 

265,500 

Mar. 

1,339,000 

2.940.000 

43.000 

0 

660,000 

679,000 

0 

408 

280,000 

April 
May 

765,000 

2,940,000 

214,000 

7.000 

609,000 

149.000 

0 

409 

266,400 

458.000 

2.940,000 

684,000 

10.000 

663.000 

0 

0 

405 

280,000 

June 

278,000 

2.704,000 

855,000 

11000 

672,000 

0 

a 

384 

280.000 

July 

231,000 

2.116.000 

941,000 

11,000 

760,000 

0 

0 

345 

280.000 

Aug. 

204.000 

1,395,000 

855,000 

8,000 

781,000 

0 

0 

292 

242.700 

Sept. 

174,000 

736.000 

513,000 

4,000 

513.000 

0 

0 

241 

131.700 

Oct. 

199,000 

303.000 

171,000 

2,000 

171.000 

0 

0 

222 

38.300 

Nov. 

924,000 

419,000 

0 

1,000 

0 

0 

0 

0 

Dec. 
Total  or 
average 

530,000 

1.342.000 

0 

0 

0 

0 

0 

0 

6.848,000 

4,276,000 

54,000 

5.5*5,000 

1.350,000 

0 

347 

176.700 

THE    CONTROL   OF   FLOODS   BY   RESERVOIRS. 


237 


RESERVOIR  ON  SACRAMENTO  RIVER. 

IRRIGATION  WITH  INCIDENTAL  POWER  GENERATION 


BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  CaFried  out  on  Daily  Basis. 

mary,  see  Table  2,  page  110.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 
Installed  capacity  of  power  plant  400,000  k.v.a.     P. F.  =  0.80. 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximiim  controlled  flow  at  Red  Bluff  125,000  seo.-ft.    M 

iximum  reservoir  space  r 

equired  454,000  ac.-ft. 

Irrigation 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

draft  in 
acre-feet 

(no 
deduction 
for  down- 
stream 
prior 
rights) 

Evapora- 
tion in 
acre-feet 

Power 

draft 

through 

turbines 

in 
acre-feet 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

irrigation 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period  of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor^ 
1.00) 

Year  and 
mouth 

1900 

1,372,000 

0 

0 

181,000 

0 

0 

0 

390 

73,800 

Jan. 

2,490.000 

0 

0 

276.000 

26,000 

0 

0 

394 

125,100 

Feb. 

2,579.000 

43,000 

0 

334,000 

279,000 

0 

0 

■    400 

137,400 

Mar. 

2,878,000 

214,000 

7,000 

388,000 

0 

0 

0 

412 

170,600 

April 

2,940,000 

684,000 

10,000 

666,000 

0 

0 

0 

404 

280,000 

May 

2,659,000 

855,000 

11,000 

675,000 

0 

0 

0 

380 

280,000 

June 

2.040,000 

941,000 

11,000 

769,000 

0 

0 

0 

339 

280,000 

July 

1,307,000 

855,000 

8,000 

772,000 

0 

0 

0 

284 

232,500 

Aug. 

652,000 

513,000 

4,000 

513.000 

0 

0 

0 

230 

124,400 

Sipt. 

338,000 

171,000 

2,000 

171,000 

0 

0 

0 

222 

38,200 

Oct. 

471.000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

837.000 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

4,276,000 

55,000 

4,745,000 

305,000 

0 

0 

342 

145,300 

1901 

1,534,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

2,429,000 

0 

0 

481,000 

711.000 

0 

0 

386 

214,700 

Feb. 

2,541,000 

43,000 

0 

387,000 

99,000 

0 

0 

398 

159,100 

Mar. 

2,804,000 

214,000 

7,000 

239,000 

0 

0 

0 

411 

105,000 

April 

2,940,000 

684,000 

10,000 

663.000 

0 

0 

0 

404 

280.000 

May 

2,657,000 

855,000 

11,000 

675,000 

0 

0 

0 

380 

280,000 

June 

2,031,000 

941,000 

11,000 

772,000 

0 

0 

0 

33J 

280,000 

July 

1,297,000 

855,000 

8,000 

769,000 

0 

0 

0 

283 

230,900 

Aug. 

640,000 

513.000 

4,000 

513,000 

0 

0 

0 

228 

123,100 

Sept. 

323,000 

171,000 

2,000 

171,000 

0 

0 

0 

211 

35,900 

Oct. 

365,000 

0 

1,000 

0 

0 

0 

0 

0 

Nov. 

718,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

54,000 

4,670,000 

810,000 

0 

0 

337 

142,000 

1902 

1,268,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

1,495,000 

0 

0 

339,000 

1,372,000 

0 

0 

379 

149,600 

Feb. 

2,566,000 

43,000 

0 

529,000 

310,000 

0 

0 

397 

218,000 

Mar. 

2,842,000 

214,000 

7,000 

552,000 

0 

231,000 

0 

409 

241,500 

April 

2,940,000 

684,000 

10,000 

660,000 

0 

105,000 

0 

409 

280,000 

May 

2,906,000 

855,000 

12,000 

654,000 

0 

0 

0 

397 

280,000 

June 

2,446,000 

941,000 

13,000 

719,000 

0 

0 

0 

366 

280,000 

July 

1,746,000 

855000 

9,000 

812,000 

0 

0 

0 

323 

280,000 

Aug. 

1,116,000 

513,000 

5,000 

513,000 

0 

0 

0 

285 

160,600 

Sept. 

782,000 

171,000 

3,000 

171,000 

0 

0 

0 

276 

50,000 

Oct. 

843,000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

1,670,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

61,000 

4,949,000 

1,682,000 

339,000 

0 

3.59 

161,600 

1903 

2,432,000 

0 

0 

442,000 

614,000 

0 

0 

387 

178,800 

Jan. 

2,489,000 

0 

0 

527.000 

47,000 

0 

0 

38J 

237,600 

Feb. 

2,.548,000 

43,000 

0 

612,000 

463,000 

0 

0 

3J5 

252,000 

Mar. 

2,812.000 

214,000 

7,000 

581,000 

25,000 

24,000 

0 

409 

253,900 

April 

2,940,000 

684,000 

10,000 

663,000 

0 

0 

0 

405 

280,000 

May 

2,704,000 

85.;,000 

11.000 

672,000 

0 

0 

0 

381 

280,000 

June 

2,116,000 

941,000 

11,000 

760,000 

0 

0 

0 

345 

280,000 

July 

1,395,000 

855,000 

8,000 

781,000 

0 

0 

0 

292 

242,700 

Aug. 

736,000 

513,000 

4,000 

513,000 

0 

0 

0 

241 

131,700 

Sept. 

393,000 

171,000 

2,000 

171,000 

0 

0 

0 

222 

38,300 

Oct. 

419,000 

0 

1,000 

0 

0 

0 

0 

0 

Nov. 

1,342,000 

0 

0 

0 

0 

0 

0 

0 

Dec 

4,276,000 

54,000 

5,722,000 

1,149,000 

24.000 

0 

345 

181,000 

Total  or 
average 

288 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  2a  (Continued).     KENNETT 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresponding  yeaily  sum 


Height  of  dam  420  feet. 

Capacity  of  reservoir  2,940,000  acre-feet. 


Estimated 

Without  flood  control 

Irrigation 

Year  and 

run-off 
at  dam 

Stage  of 
reservoir 

draft  in 
acre-feet 

Power 

draft 

through 

turbines 

Waste 

De6cienoy 

Average 
power 

Average 
power 

month 

site  in 

at 

Tno 

Evapora- 

over 

HI 

head 

jield  in 

acre-feet 

beginning 

deduction 

tion  in 

spillway 

irrigation 
supply 

through 

kilowatts 

of 

for  down- 

acre-feet 

in 

period  of 

(Load 

month  in 
acre-feet 

stream 
prior 

in 
acre-feel 

acre-feet 

in 
acre-feet 

operation 
in  feet 

factor^ 
1.00) 

rights) 

1904 

Jan. 

473,000 

1,872,000 

0 

0 

0 

0 

0 

0 

Feb. 

1.742,000 

2,345,000 

0 

0 

281,000 

866,000 

0 

400 

125,100 

Mar. 

2,877,000 

2,940,000 

43,000 

0 

670,000 

2,207,000 

0 

400 

280.000 

April 

1,467,000 

2,940,000 

214,000 

7,000 

645,000 

81.5,000 

0 

402 

280.000 

May 

914,000 

2,940,000 

684,000 

10,000 

660,000 

220,000 

0 

407 

280,000 

June 

.505,000 

2,940,000 

855,000 

12,000 

648,000 

0 

0 

400 

280.000 

July 

377,000 

2,578,000 

941,000 

13.000 

704,000 

0 

0 

376 

280,000 

Aug. 

282.000 

2,001,000 

8.5f,000 

10,000 

763,000 

0 

0 

342 

280,000 

Sept. 

271,000 

1,418,000 

513,000 

6,000 

513.000 

0 

0 

316 

178.300 

Oct. 

491,000 

1,170,000 

171,000 

4,000 

171,000 

0 

0 

322 

58,600 

Nov. 

379,000 

1,486,000 

0 

3,000 

0 

0 

0 

0 

Dec. 

600,000 

1,862,000 

0 

0 

0 

0 

0 

0 

Total  or 

average 

10,378,000 

4,276,000 

65,000 

5,055,000 

4,108,000 

0 

372 

170,200 

1905 

Jan. 

1,371,000 

2,462,000 

0 

0 

315,000 

578.000 

0 

404 

132,100 

Feb. 

1,027,000 

2,940.000 

0 

0 

596,000 

431,000 

0 

407 

278,300 

Mar. 

1,33.5,000 

2,940,000 

43,000 

0 

649,000 

686,000 

0 

406 

273,500 

April 

7.53,000 

2,940,000 

214.000 

7,000 

619,000 

127,000 

0 

409 

270,800 

May 

560,000 

2,940,000 

684,000 

10,000 

660,000 

0 

0 

408 

280,000 

June 

365,000 

2.806,000 

855,000 

11,000 

660,000 

0 

0 

391 

280.000 

July 

269,000 

2,305,000 

941,000 

12,000 

735,000 

0 

0 

358 

280.000 

Aug. 

236,000 

1  621.000 

8.55,000 

9,000 

809,000 

0 

0 

313 

270,200 

Sept. 

208,000 

993,000 

513,000 

5,000 

513,000 

0 

0 

274 

153,800 

Oct. 

221,000 

683,000 

171,000 

3,000 

171,000 

0 

0 

264 

47,600 

Nov. 

229,000 

730,000 

0 

2,000 

0 

0 

0 

0 

Dec. 

249.000 

957,000 

0 

0 

0 

0 

0 

0 

Total  or 

avei  age 

6,823,000 

4,276,000 

59,000 

5,727,000 

1,822,000 

0 

361 

188,300 

1906 

Jan. 

851,000 

1,206.000 

0 

0 

0 

0 

0 

0 

Feb. 

872,000 

2,057,000 

0 

0 

0 

0 

■0 

0 

Mar. 

1,646,000 

2,92'.>,000 

43,000 

0 

f57,O0O 

978,000 

0 

409 

280,000 

April 

995,000 

2,940,000 

214,000 

7.000 

642,000 

346,000 

0 

406 

280,000 

May 

817.000 

2,940,000 

684,000 

10,000 

660,000 

123,000 

0 

407 

280,000 

June 

756,000 

2,940,000 

855,000 

12,000 

641,000 

44,000 

0 

406 

280,000 

July 

362,000 

2,785,000 

941,000 

14,000 

688,000 

0 

0 

387 

280.000 

Aug. 

280,000 

2,192,000 

855,000 

11,000 

741,000 

0 

0 

354 

280.000 

(Sept. 

247.000 

1,606,000 

513.000 

7.000 

513.000 

0 

0 

329 

186,000 

Oct. 

251,000 

1,533,000 

171,000 

5  000 

171.000 

0 

0 

326 

59,300 

Nov. 

256,000 

1,408,000 

0 

3,000 

0 

0 

0 

0 

Dec. 

648,000 

1,661,000 

0 

0 

0 

0 

0 

0 

Total  or 
average 

7,981,000 

4.276.000 

60,000 

4,713.000 

1.491,000 

0 

378 

161,500 

1907 

Jan. 

936,000 

2,309.000 

0 

0 

140,000 

165,000 

0 

407 

59,100 

Feb. 

1.636,000 

2,940,000 

0 

0 

602,000 

1.034,000 

0 

403 

280,000 

Mar. 

2,115,000 

2,940,000 

43,000 

0 

()66,000 

1,449.000 

0 

403 

280,000 

April 
May 

1,250,000 

2,940,000 

214,000 

7,000 

642,000 

601.000 

0 

404 

280,000 

646,000 

2,940.000 

684.000 

10,000 

658,000 

8,000 

0 

409 

280,000 

Juno 

421,000 

2,884,000 

855.000 

12,000 

651,000 

0 

0 

3J6 

280,000 

July 

334,000 

2,438.000 

941,000 

13,000 

716,000 

0 

0 

368 

280,000 

Aug. 

291,000 

1,818,000 

85,5,000 

10.000 

790,000 

0 

0 

331 

280,000 

Sept. 

252.000 

1,244,000 

513,000 

6,001) 

f  13,000 

0 

0 

301 

169,700 

Oct. 

261,000 

977,000 

171,000 

4,000 

171,000 

0 

0 

296 

53,900 

Nov. 

256,000 

1,063,000 

0 

3,000 

0 

0 

0 

0 

Dec. 
Total  or 
average 

479,000 

1.316,000 

0 

0 

0 

0 

0 

0 

8.877,000 

4,'?76,000 

65,000 

5,552,000 

3,257,000 

0 

369 

186.200 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


239 


RESERVOIR  ON  SACRAMENTO  RIVER. 

IRRIGATION  WITH  INCIDENTAL  POWER  GENERATION 


BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  2,  page  1 10.) 

Seasona    irrigation  yield  (deficiency  in  supp  y  one  year  in    en,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 
Installed  capacity  of  power  plant  400,000  k.v.a.     P.P.  =  0.80. 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum 

controlled  flow  at  Red  Bluff  125,033 

sec.-ft.    Maximum  reservoir  space  required  454,000  ac.-ft. 

Irrigation 

Stage  of 
reservoir 

draft  in 
acre-feet 

Power 

draft 

through 

turbines 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 

Deficiency 

Average 
power 

Average 
power 

Year  and 

at 

beginning 

of 

(no 
deduction 
for  down- 

Evapora- 
tion in 
acre-feet 

over 

spillway 

in 

in 

irrigation 
supply 

head 
through 
period  of 

yield  in 

kilowatts 

(Load 

month 

month  in 
acre-feet 

stream 
prior 

in 

acre-feet 

acre-feet 

in 
acre-feet 

operation 
in  feet 

factor= 
1.00) 

rights) 

1904 

1,872,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

2,345,000 

0 

0 

363,000 

1,194,000 

0 

0 

38i 

155,300 

Feb. 

2,530,000 

43,000 

0 

688,000 

1,861.000 

0 

0 

387 

280,000 

Mar. 

2,858,000 

214,000 

7,000 

642,000 

115,000 

621.000 

0 

405 

280,000 

April 

2,940,000 

684,000 

10,000 

660,000 

0 

220,000 

0 

407 

280,000 

May 

2,940,000 

855,000 

12,000 

648,000 

0 

0 

0 

400 

280,000 

June 

2,578,000 

941,000 

13,000 

704,000 

0 

0 

0 

376 

280,000 

July 

2,001,000 

855,000 

10,000 

763,000 

0 

0 

0 

342 

280,000 

Aug. 

1,418,000 

513,000 

6,000 

513,000 

0 

0 

0 

316 

178,300 

Sept. 

1,170,000 

171,000 

4,000 

171,000 

0 

0 

0 

322 

58,600 

Oct. 

1,486,000 

0 

3,000 

0 

0 

0 

0 

0 

Nov. 

1,862,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

65,000 

5,152,000 

3,170,000 

841,000 

0 

370 

172,600 

1905 

2,462,000 

0 

0 

545,000 

656,000 

0 

0 

390 

222,700 

Jan. 

2,632,000 

0 

0 

591,000 

469,000 

0 

0 

393 

268,600 

Feb. 

2,599,000 

43,000 

0 

606,000 

407,000 

0 

0 

398 

250,900 

Mar. 

2,921.000 

214,000 

7,000 

618,000 

18,000 

91,000 

0 

409 

270,800 

April 

2,940,000 

684,000 

10.000 

660,000 

0 

0 

0 

408 

280,000 

May 

2,806,000 

855,000 

11,000 

660,000 

0 

0 

0 

391 

280,000 

June 

2,305,000 

941,000 

12,000 

735,000 

0 

0 

0 

358 

280,000 

July 

1,621,000 

855,000 

9,000 

809,000 

0 

0 

0 

313 

270,200 

Aug. 

993,000 

513,000 

5,000 

513,000 

0 

0 

0 

274 

153.800 

Sapt. 

683,000 

171,000 

3,000 

171,000 

0 

0 

0 

264 

47,600 

Oct. 

730,000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

957,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

59,000 

5,908,000 

1,550,000 

91,000 

0 

359 

193,300 

190S 

1.206,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

2,057,000 

0 

0 

117,000 

206,000 

0 

0 

392 

53,300 

Feb. 

2,606,000 

43,000 

0 

627,000 

790,000 

0 

0 

394 

257,900 

Mar. 

2,835,000 

214,000 

7,000 

640,000 

104,000 

139,000 

0 

407 

280,000 

April 

2,940,000 

684,000 

10,000 

660,000 

0 

123,000 

0 

407 

280,000 

May 

2,940,000 

855,000 

12,000 

641,000 

0 

44,000 

0 

406 

280,000 

June 

2,78f,000 

941,000 

14,000 

688,000 

0 

0 

0 

387 

280,000 

July 

2,192,000 

855,000 

11,000 

741,000 

0 

0 

0 

354 

280,000 

Aug. 

1,606,000 

513,000 

7,000 

513,000 

0 

0 

0 

32C 

186,000 

Sept. 

1,333,000 

171,000 

5,000 

171,000 

0 

0 

0 

326 

59,300 

Oct. 

1,408,000 

0 

3,000 

0 

0 

0 

0 

0 

Nov 

1,661,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

4,276,000 

69,000 

4,798,000 

1,100.000 

306,000 

0 

377 

163,700 

1907 

2,S09,000 

0 

0 

539,000 

218,000 

0 

0 

389 

219,600 

Jan. 

2,488,000 

0 

0 

626,000 

968,000 

0 

0 

384 

280,000 

Feb. 

2,530,000 

43,000 

0 

680,000 

1,147,000 

0 

0 

392 

278,600 

Mar. 

2,818,000 

214,000 

7,000 

642,000 

135,000 

344,000 

0 

404 

280,000 

April 

2,940,000 

684,000 

10,000 

6.58,000 

0 

8,000 

0 

409 

280,000 

May 

2,884,000 

855,000 

12,000 

6.54,000 

0 

0 

0 

3;)6 

280,000 

June 

2,438,000 

941,000 

13,000 

716,000 

0 

0 

0 

368 

280,000 

July 

1,818,000 

855,000 

10,000 

790,000 

0 

0 

0 

331 

280,000 

Aug. 

1,244.000 

513,000 

6,000 

513,000 

0 

0 

0 

301 

169,700 

Sept. 

977,000 

171,000 

4,000 

i;  1,000 

0 

0 

0 

296 

53,000 

Oct. 

1,063,000 

0 

3,000 

0 

0 

0 

0 

0 

Nov. 

1,316,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

65.000 

5,989,000 

2,468,000 

352,000 

0 

366 

199,700 

240 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  2a  (Continued).     KENNETT 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet. 

Capacity  of  reservoir  2,940,000  acre-feet. 


Estimated 

Withcut  flood  control 

Irrigation 

run-off 

Stage  of 

draft  in 

Power 

draft 

through 

turbines 

Deficiency 

Average 

Average 

Year  and 

at  dam 

reseivoir 

acre-feet 

Waste 

power 

power 

month 

site  in 

at 

(no 

Evapora- 

over 

in 

head 

yield  in 

acre-feet 

beginning 

deduction 

tion  in 

spillway 

irrigation 
supply 

through 

lalowatts 

of 

for  down- 

acre-feet 

in 

period  of 

(Load 

month  in 
acre-feet 

stream 
prior 
rights) 

in 
acre-feet 

acre-feet 

in 
acre-feet 

operation 
infect 

factor=: 
1.00) 

1908 

Jan. 

904,000 

1,795,000 

0 

0 

0 

0 

0 

0 

Feb. 

970,000 

2,699,000 

0 

0 

472,000 

257,000 

0 

409 

213,100 

Mar. 

669,000 

2,940,000 

43,000 

0 

624.000 

45,000 

0 

410 

264,300 

April 

527,000 

2,940,000 

214,000 

7,000 

520,000 

0 

0 

411 

227.900 

May 

492,000 

2,940,000 

684.000 

10,000 

663.000 

0 

0 

406 

280.000 

June 

340,000 

2,738,000 

855.000 

11,000 

666,000 

0 

0 

387 

280,000 

July 

'260,000 

2,212,000 

941.000 

12,000 

744,000 

0 

0 

352 

280.000 

Aug. 

229,000 

1,519,000 

855,000 

8,000 

797,000 

0 

0 

305 

258,500 

Sept. 

205,000 

885,000 

513,000 

5.000 

513.000 

0 

0 

262 

146.000 

Oct. 

235,000 

572,000 

171,000 

3,000 

171,000 

0 

0 

251 

44,800 

Nov. 

257,000 

633,000 

0 

2,000 

0 

0 

0 

0 

Dec. 

267,000 

888,000 

0 

0 

0 

0 

0 

0 

Total  or 
average 

5,355,000 

4,276.000 

58,000 

5,170,000 

302,000 

0 

353 

166,000 

1909 

Jan. 

3,260.000 

1,155,000 

0 

0 

282,000 

1,193,000 

0 

397 

117,100 

Feb. 

2,526,000 

2,940.000 

0 

0 

605,000 

1,921,000 

0 

400 

280.000 

Mar. 

977,000 

2,940,000 

43.000 

0 

666,000 

311,000 

0 

404 

280.000 

April 

756,000 

2,940,000 

214,000 

7,000 

636,000 

113,000 

0 

409 

280.000 

May 

581,000 

2,940,000 

684,000 

10,000 

659,000 

5,000 

0 

408 

280,000 

June 

410,000 

2,822.000 

855,000 

11,000 

657,000 

0 

0 

393 

280.000 

July 

308,000 

2,366,000 

941,000 

12,000 

725.000 

0 

0 

363 

280.000 

Aug. 

264,000 

1,721,000 

855,000 

9,000 

809.000 

0 

0 

323 

280.000 

Sept. 

246,000 

1,121,000 

513,000 

5.000 

513,000 

0 

0 

289 

163,100 

Oct. 

284,000 

849,000 

171,000 

3,000 

171.000 

0 

0 

286 

51,700 

Nov. 

538.000 

959,000 

0 

2,000 

0 

0 

0 

0 

Dec. 
Total  or 
average 

721,000 

1,495,000 

0 

0 

0 

0 

0 

0 

10,871,000 

4,276,000 

59,000 

5.723,000 

3.543.000 

0 

362 

190,400 

1910 

Jan. 

708,000 

2.216.000 

0 

0 

0 

0 

0 

0 

Feb. 

847,000 

2,924,000 

0 

0 

551.000 

280.000 

0 

409 

257,400 

Mar. 

1,239,000 

2,940,000 

43,000 

0 

663.000 

576.000 

0 

405 

280,000 

April 

665,000 

2,940,000 

214,000 

7,000 

603.000 

55.000 

0 

411 

264,900 

May 

41S.000 

2,940,000 

684,000 

10,000 

663.000 

0 

0 

405 

280,000 

June 

282,000 

2,661,000 

855,000 

11,000 

675.000 

0 

0 

381 

280,000 

July 

254,000 

2,077.000 

941,000 

11,000 

763.000 

0 

0 

344 

280.000 

Aug. 

236,000 

1,379,000 

855,000 

8,000 

781.000 

0 

0 

292 

242.600 

"Sept. 

214.000 

752,000 

513,000 

4,000 

513.000 

0 

0 

246 

135.400 

Oct. 

231,000 

449.000 

171,000 

2,000 

171.000 

0 

0 

234 

41,000 

Nov. 

274.000 

507.000 

0 

2,000 

0 

0 

0 

0 

Dec. 
Total  or 
avefage 

436,000 

779.000 

0 

0 

0 

0 

0 

0 

5,801,000 

4.276.000 

£5,000 

5.383.000 

911.000 

0 

347 

171,100 

1911 

Jan. 

700,000 

1.215,000 

0 

0 

0 

0 

0 

0 

Feb. 

848,000 

1,915,000 

0 

0 

0 

0 

0 

0 

Mar. 

1.278,000 

2,763.000 

43,000 

0 

562,000 

539,000 

0 

407 

237,000 

April 
May 

962,000 

2.940.000 

214,000 

7,000 

639,000 

316,000 

0 

408 

280,000 

671,000 

2.940.000 

684,000 

10,000 

657,000 

13,000 

0 

410 

280,000 

June 

431.000 

2,904,000 

855,000 

12,000 

654,000 

0 

0 

397 

280,000 

July 

287.000 

2,468,000 

941,000 

13,000 

716,000 

0 

0 

368 

280,000 

Aug. 

244.000 

1,801,000 

855,000 

10.000 

797,000 

0 

0 

328 

280,000 

Sept 

231,000 

1,180,000 

513.000 

6,000 

513,000 

0 

0 

294 

165,600 

Oct. 

246,000 

892.000 

171,000 

3,000 

171,000 

0 

0 

288 

52,300 

Nov. 

241,000 

964.000 

0 

2,000 

0 

0 

0 

0 

Dec. 
Total  or 
average 

244,000 

1.203,000 

0 

0 

0 

0 

0 

0 

6,383,000 

4,276,000 

63,000 

4,709.000 

868.000 

0 

362 

155,500 

THE    CUK'T'ROu   OF    FLOODS   BY    RESERVOIRS. 


241 


RESERVOIR  ON  SACRAMENTO  RIVER. 

IRRIGATION  WITH  INCIDENTAL  POWER  GENERATION 


BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Dail>  Basis. 

mary,  see  Table  2,  page  1 10.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 

Installed  capacity  of  power  plant  400,000  k.v.a.     P.P.  =0.80. 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  f 

ow  at  Red  Bluff  125,000 

sec.-ft.    Maximum  reservoir  space  re 

quired  454,000  ac.-ft. 

Irrigation 

Stage  of 
reservoir 

at 
beginning 

of 

draft  in 
acre-feet 

(no 
deduction 
for  down- 

Evapora- 
tion in 
acre-feet 

Power 

draft 

through 

turbines 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 

over 

spillway 

in 

Deficiency 

in 

irrigation 

supply 

Average 

power 

head 

through 

period  of 

Average 
power 

yield  in 

lulowatts 

(Load 

Year  and 
month 

month  in 
acre-feet 

stream 
prior 

in 
acre-feet 

acre-feet 

in 
acre-feet 

operation 
in  feet 

factor= 
1.00) 

rights) 

1908 

1,795,000 

0 

0 

44,000 

0 

0 

0 

399 

18,100 

Jan. 

2,655,000 

0 

0 

536,000 

537,000 

0 

0 

388 

232,200 

Feb. 

2,552,000 

43,000 

0 

311,000 

16,000 

0 

0 

401 

128,900 

Mar. 

2,894,000 

214,000 

7,000 

474,000 

0 

0 

0 

411 

207,800 

April 

2,940,000 

684,000 

10,000 

663,000 

0 

0 

0 

406 

280,000 

May 

2,738,000 

855,000 

11,000 

666,000 

0 

0 

0 

387 

280,000 

Jane 

2,212,000 

941,000 

12,000 

744,000 

0 

0 

0 

352 

280,000 

July 

1,519,000 

855,000 

8,000 

797,000 

0 

0 

0 

305 

258,500 

Aug. 

885,000 

513,000 

5,000 

513,000 

0 

0 

0 

262 

146,000 

S^pt. 

572,000 

171,000 

3,000 

171,000 

0 

0 

0 

251 

44,800 

Oct. 

633,000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

888,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 

4,276,000 

58,000 

4,919,000 

553,000 

0 

0 

352 

155,900 

average 
1909 

1,155,000 

0 

0 

321,000 

1,588,000 

0 

0 

381 

128,600 

Jan. 

2,506,000 

0 

0 

623,000 

1,784,000 

0 

0 

386 

280,000 

Feb. 

2,625,000 

43,000 

0 

543,000 

150,000 

0 

0 

401 

225,800 

Mar. 

2,909,000 

214,000 

7,000 

027,000 

2,000 

89,000 

0 

409 

2/5,300 

April 

2,940,000 

684,000 

10,000 

659,000 

0 

5,000 

0 

408 

280,000 

May 

2,822,000 

855,000 

11,000 

657,000 

0 

0 

0 

3i)3 

280,000 

June 

2,366,000 

941,000 

12,000 

725,000 

0 

0 

0 

363 

280.000 

July 

1,721,000 

855,000 

9,000 

809,000 

0 

0 

0 

323 

280,000 

Aug. 

1,121,000 

513.000 

5,000 

513,000 

0 

0 

0 

289 

163,100 

Sept. 

849,000 

171,000 

3,000 

ia,ooo 

0 

0 

0 

286 

51,700 

Oct. 

959,000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

1,495,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 

4,276,000 

50,000 

5,648,000 

3,524,000 

94,000 

0 

363 

186,400 

average 
1910 

2,216,000 

0 

0 

154,000 

126,000 

0 

0 

393 

63,200 

Jan. 

2,644,000 

0 

0 

414,000 

303,000 

0 

0 

399 

190,300 

Feb. 

2,774,000 

43,000 

0 

632,000 

279,000 

162,000 

0 

406 

205, ZOO 

Mar. 

2,940,000 

214,000 

7,000 

603,000 

0 

55,000 

0 

411 

264,900 

April 

2,940,000 

684,000 

10,000 

663,000 

0 

0 

0 

405 

280,000 

May 

2,661,000 

855,000 

11,000 

075,000 

0 

0 

0 

381 

280,000 

June 

2,077,000 

941,000 

11,000 

763,000 

0 

0 

0 

344 

280,000 

July 

1,379,000 

855,000 

8,000 

781,000 

0 

0 

0 

292 

212.600 

Aug. 

752,000 

513,000 

4,000 

513,000 

0 

0 

0 

240 

135,400 

Sept. 

449,000 

171,000 

2,000 

171,000 

0 

0 

0 

234 

41,000 

Oct. 

507,000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

779,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 

4,276,000 

55,000 

5,369.000 

708,000 

217,000 

0 

317 

170,100 

average 
1911 

1,215,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

1,915,000 

0 

0 

167,000 

5,000 

0 

0 

394 

75,600 

Feb. 

2,591,000 

43,000 

0 

639,000 

417.000 

0 

0 

395 

263,200 

Mar. 

2,813,000 

214,000 

7,000 

638,000 

59,000 

131,000 

0 

407 

278,300 

April 

2,940,000 

684,000 

10,000 

657,000 

0 

13,000 

0 

410 

280,000 

May 

2,904,000 

855,000 

12.000 

654,000 

0 

0 

0 

397 

280,000 

June 

2,468,000 

941,000 

13,000 

716,000 

0 

0 

0 

368 

280,000 

July 

1,801,000 

855,000 

10,000 

797,000 

0 

0 

0 

328 

280,000 

Aug. 

1,180,000 

513,000 

b,000 

513,000 

0 

0 

0 

294 

165,600 

Sept. 

892,000 

171,000 

3,000 

171,000 

0 

0 

0 

288 

52,300 

Oct. 

964,000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

1,203,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 

4,276,000 

63,000 

4,952,000 

481.000 

144,000 

0 

363 

163,400 

average 

';>j.-> 


WATER  RESOURCES   OF    CALIFORNIA. 


TABLE  2a  fContinued).     KENNETT 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet. 

Capacity  of  reservoir  2,9'10,000  acre-feet. 


Estimated 

Without  flood  control 

Irrigation 

run-off 

Stage  of 

draft  in 

Power 

draft 

through 

turbines 

Deficiency 

.\verage 

Average 

Year  and 

at  dam 

reservoir 

acre-feet 

Waste 

power 

power 

month 

site  in 

at 

(no 

Evapora- 

over 

in 

irrigation 

supply 

head 

yield  in 

acre-feet 

beginning 
of 

deduction 
for  down- 

tion in 
acre-feet 

spillway 
in 

through 
period  of 

kilowatts 
(Load 

month  in 
acre-feet 

stream 
prior 

in 
aci e-fcet 

acre-feet 

in 
acre-feet 

operation 
in  feet 

factor= 
1.00) 

rights) 

1912 

Jan. 

.517,000 

1,447,000 

0 

0 

0 

0 

0 

0 

Feb. 

396,000 

1,964,000 

0 

0 

0 

0 

0 

0 

Mar. 

635,000 

2,360,000 

43,000 

0 

55,000 

0 

0 

402 

23.000 

April 

487,000 

2,940,000 

214,000 

7,000 

455,000 

25.000 

0 

411 

199,900 

May 

714,000 

2,940,000 

684,000 

10.000 

659,000 

58,000 

0 

408 

280.000 

.lune 

405.000 

2,902,000 

855.000 

12.000 

654,000 

0 

0 

396 

280.000 

July 

274.000 

2,440,000 

941,000 

13.000 

719,000 

0 

0 

366 

280.000 

Aug. 

238,000 

1,760,000 

855,000 

9.000 

806.000 

0 

0 

325 

280,000 

Sept. 

242,000 

1,134,000 

513,000 

5,000 

513,000 

0 

0 

290 

163,600 

Oct. 

226,000 

858.000 

171,000 

3,000 

171,000 

0 

0 

284 

51,500 

Nov. 

432,000 

910,000 

0 

2,000 

0 

0 

0 

0 

Dec. 
Total  or 
average 

369,000 

1,340,000 

0 

0 

0 

0 

0 

0 

4,935,000 

4,276,000 

61,000 

4,032,000 

83,000 

0 

360 

130,200 

1913 

Jan. 

763,000 

1,709,000 

0 

0 

0 

0 

0 

0 

Feb. 

387,000 

2,472,000 

0 

0 

0 

0 

0 

0 

Mar. 

441,000 

2.859,000 

43,000 

0 

3.54,000 

6,000 

0 

412 

1.50.400 

April 

685,000 

2,940,000 

214,000 

7.000 

626,000 

52.000 

0 

410 

274,300 

May 

521,000 

2,940,000 

684,000 

10,000 

663,000 

0 

0 

406 

280,000 

June 

321,000 

2,767,000 

85.^000 

11.000 

666,000 

0 

0 

388 

280,000 

July 

263,000 

2.222,000 

941,000 

12.000 

744,000 

0 

0 

352 

280.000 

Aug. 

232,000 

1,532,000 

855,000 

8,000 

800,000 

0 

0 

306 

260.400 

Sept. 

190,000 

901,000 

513,000 

5,000 

513.000 

0 

0 

263 

14fi..50O 

Oct. 

202,000 

573,000 

171,000 

3,000 

171,000 

0 

0 

249 

44..500 

Nov. 

316,000 

601,000 

0 

2,000 

0 

0 

0 

0 

Dec. 
Total  or 
average 

696,000 

915,000 

0 

0 

0 

0 

0 

0 

5.017,000 

4,276,000 

58,000 

4,537,000 

58,000 

0 

348 

143,800 

1914 

Jan. 

2,797,000 

1,611,000 

0 

0 

346.000 

1,122,000 

0 

399 

144,100 

Feb. 

1,359,000 

2,940,000 

0 

0 

592,000 

767,000 

0 

406 

275,700 

Mar. 

987,000 

2,940,000 

43,000 

0 

600,000 

327,000 

0 

407 

280,000 

April 

1,137.000 

2,940,000 

214,000 

7,000 

639,000 

491.000 

0 

407 

278,600 

May 

703,000 

2,940,000 

684,000 

10,000 

657,000 

37.000 

0 

409 

280.000 

June 

452.000 

2.912,000 

855,000 

12.000 

651,000 

0 

0 

398 

280,000 

July 

309,000 

2,497,000 

941,000 

13,000 

713,000 

0 

0 

370 

280,000 

Aug. 

248,000 

1,8.52,000 

855,000 

10.000 

787,000 

0 

0 

332 

280,000 

Sept. 

225.000 

1,235,000 

513,000 

0,000 

513,000 

0 

0 

298 

168.300 

Oct. 

269.000 

941,000 

171,000 

4,000 

171,000 

0 

0 

294 

53,400 

Nov. 

2.52,000 

1,035,000 

0 

3,000 

0 

0 

0 

0 

Dec. 
Total  or 
average 

347,000 

1.284,000 

0 

4,276.000 

0 

0 

0 

0 

0 

9.085.000 

65,000 

5,729,000 

2,744,000 

0 

370 

192.800 

1915 

Jan. 

895.000 

1,631,000 

0 

0 

0 

0 

0 

0 

Feb. 

2,298.000 

2,526,000 

0 

0 

682,000 

1,302,000 

0 

402 

269.200 

Mar. 

1,264,000 

2,940,000 

43,000 

0 

666.000 

598,000 

0 

404 

280,000 

April 

1,159,000 

2,940,000 

214,000 

7,000 

642,000 

510,000 

0 

406 

280,000 

May 

1,2.W.00() 

2,940.000 

684,000 

10,000 

ti()2,00() 

562,000 

0 

406 

280,000 

June 

572.000 

2,940,000 

855.000 

12.000 

()45,000 

0 

0 

403 

280.000 

July 

343,(H)0 

2,645,000 

941,000 

14.000 

701,000 

0 

0 

379 

280.000 

Aug. 

266.000 

2.033,(X)O 

8.55,000 

10.000 

75il,()00 

0 

0 

344 

280,000 

Sopl. 

215.000 

1.4;}4,0OO 

513.000 

6,000 

513,000 

0 

0 

314 

177,.500 

Oct. 

233,000 

i.i.mooo 

171,000 

4.000 

171.000 

0 

0 

309 

56,000 

Nov. 

.  254,000 

1,188,000 

0 

3.000 

0 

0 

0 

0 

Dec. 
Total  or 
average 

699,000 

1,439,000 

0 

0 

0 

0 

0 

374 

0 

9.-.64,0OO 

4,276,000 

66.000 

5,341,000 

2.972.000 

0 

181,100 

THE    CONTROL   OF    FLOODS    BY    RESERVOIKS. 


243 


RESERVOIR  ON  SACRAMENTO  RIVER. 

IRRIGATION  WITH  INCIDENTAL  POWER  GENERATION 


BY  RESERVOIR  OPERATING  DIAGRAM. 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  2,  page  1 10.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 
Installed  capacity  of  power  p  ant  400,000  k.v.a.     P.P.  =  0.80. 


Coordinated  with  flood  control  by  res 

srvolr  operating  diagram 

Maximurr 

controlled  flow  at  Red  Bluff  125,000 

sec.-ft.     Maximum  reservoir  space  required  451,000  ac.-ft. 

Irrigation 

Stage  of 
reservoir 

draft  in 
acre-feet 

Power 

draft 

through 

turbines 

Release 
through 
flood 
control 
Oiitletsin 
acre-feet 

Waste 

Deficiency 

Average 
power 

.\verage 
power 

Year  and 

at         I 
b3ginning 
of 

'no 
deduction 
for  down- 

Evapora- 
tion in 
acre-feet 

over 

spillway 

in 

in 

irrigation 

supply 

head 
through 
period  of 

yield  in 

lulowatts 

(Load 

month 

month  in 
acre-feet 

stream 
prior 

in 
acre-feet 

acre-feet 

in 
acre-fe3t 

operation 
in  feet 

facto:= 
1.00) 

rights) 

1912 

1.447.000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

1.9M.000 

0 

0 

0 

0 

0 

0 

0 

Feb. 

2,.360.000 

43,000 

0 

55.000 

0 

0 

0 

402 

23,000 

Mar. 

2.940,000 

214,000 

7,000 

4.55,000 

0 

25,000 

0 

411 

199.900 

April 

2,940.000 

684,000 

10,000 

6^9,000 

0 

58,000 

0 

408 

280.000 

May 

2.902.000 

855,000 

12,000 

654,000 

0 

0 

0 

396 

280,000 

June 

2,440,000 

941,000 

13,000 

719,000 

0 

0 

0 

366 

280,000 

July 

1,760,000 

855,000 

9,000 

80fi,000 

0 

0 

0 

325 

280,000 

Aug. 

1.134,000 

513,000 

5.000 

513,000 

0 

0 

0 

290 

163,600 

Sspt. 

8.58.000 

171,000 

3,000 

171,000 

0 

0 

0 

284 

51,500 

Oct. 

910.000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

1.340.000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

61,000 

4,032,000 

0 

83,000 

0 

360 

130,200 

1913 

1,709,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

2,472,000 

0 

0 

135,000 

0 

0 

0 

400 

62,500 

Feb. 

2.724,000 

43,000 

0 

215,000 

10,000 

0 

0 

410 

91.500 

Mar. 

2,940,000 

214,000 

7,000 

626.000 

0 

52,000 

0 

40D 

274,300 

.A.pril 

2.940,000 

684,000 

10,000 

663,000 

0 

0 

0 

406 

280,000 

May 

2.767,000 

8.55,000 

11,000 

666,000 

0 

0 

0 

388 

280,000 

June 

2.222,000 

941,000 

12,000 

744.000 

0 

0 

0 

352 

280.000 

July 

1,.532,000 

855,000 

8,000 

800,000 

0 

0 

0 

308 

260.400 

Aug. 

901.000 

513.000 

5,000 

.bl3,000 

0 

0 

0 

263 

146.500 

Sept. 

.573,000 

171,000 

3,000 

171,000 

0 

0 

0 

249 

44.500 

Oct. 

601,000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

915.000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

58,000 

4,533,000 

10.000 

52,000 

0 

352 

143,600 

1914 

1.611.000 

0 

0 

416,000 

1.213.000 

0 

0 

394 

171.100 

Jan. 

2,779.000 

0 

0 

612,000 

752.000 

0 

0 

394 

280,000 

Feb. 

2,774,000 

43,000 

0 

614,000 

249,000 

0 

0 

401 

255,800 

Mar. 

2,898,000 

214,000 

7,000 

627,000 

0 

461,000 

0 

407 

273.200 

.\pril 

2,940,000 

684.000 

10,000 

657,000 

0 

37,000 

0 

409 

280.000 

May 

2.912,000 

855,000 

12,000 

651,000 

0 

0 

0 

338 

280.000 

June 

2,497.000 

941,000 

13,000 

713.000 

0 

0 

0 

370 

280,000 

July 

1,852.000 

855.000 

10,000 

787.000 

0 

0 

0 

332 

280,000 

Aug. 

1.235,000 

513,000 

6,000 

513,000 

0 

0 

0 

298 

168.300 

S3pt. 

941,000 

171,000 

4,000 

171,000 

0 

0 

0 

294 

53,400 

Oct. 

1,035,000 

0 

3,000 

0 

0 

0 

0 

0 

Nov. 

1,284,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

65,000 

5,761.000 

2.214,000 

498,000 

0 

369 

192,900 

1915 

1,631,000 

0 

0 

22,000 

16,000 

0 

0 

38S 

9,000 

Jan. 

2,488,000 

0 

0 

620,000 

1,475,000 

0 

0 

386 

278,100 

Feb. 

2,691,000 

43,000 

0 

655,000 

373,000 

0 

0 

399 

271,900 

Mar. 

2,927,000 

214,000 

7,000 

642,000 

32,000 

465,000 

0 

405 

280,000 

April 

2,940.000 

684,000 

10,000 

662,000 

0 

562,000 

0 

406 

280,000 

May 

2,940.000 

855,000 

12,000 

645,000 

0 

0 

0 

403 

280,000 

June 

2,645,000 

941,000 

14,000 

701,000 

0 

0 

0 

379 

280,000 

July 

2,033,000 

855,000 

I        10,000 

7.59,000 

0 

0 

0 

344 

280,000 

Aug. 

1,434,000 

513.000 

0,000 

51b,000 

0 

0 

0 

314 

177,.500 

Sept. 

1,130,000 

171,000 

'          4,000 

171,000 

0 

0 

0 

309 

56,000 

Oct. 

1,188,000 

0 

3,000 

i                0 

0 

0 

0 

0 

Nov. 

1.439.000 

0 

'                0 

!        0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

4,276,000 

66,000 

5,390,000 

1,896,000 

1,027,000 

0 

372 

181,900 

244 


WATER  RESOURCES   OF    CALIFORNIA. 


TABLE  2a  (Continued).     KENNETT 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet. 

Capacity  of  reservoir  2,940,000  acre-feet. 


Estimated 

Without  flood  control 

Irrigation 

Year  and 

run-off 
at  dam 

Stage  of 
reservoir 

draft  in 
acre-feet 

Power 

draft 

through 

turbines 

Waste 

Deficiency 

Average 
power 

Average 
power 

month 

site  in 
acre-feet 

at 

beginning 

of 

(no 
deduction 
for  down- 

Evapora- 
tion in 
acre-feet 

over 

spillway 

in 

in 

irrigation 

supply 

head 
through 
period  of 

yield  in 

kilowatts 

(Load 

month  in 
acre-feet 

stream 
prior 
rights) 

in 
acre-feet 

acre-feet 

in 
acre-feet 

operation 
in  feet 

factor= 
1.00) 

1916 

Jan. 

1.166,000 

2,138,000 

0 

0 

171,000 

193,000 

0 

406 

72,000 

Feb. 

1,616.000 

2,940,000 

0 

0 

620.000 

996,000 

0 

404 

277.900 

Mar. 

1,21.5.000 

2,940,000 

43,000 

0 

663.000 

552,000 

0 

406 

280,000 

April 

678,000 

2.940,000 

214.000 

7,000 

614.000 

57.000 

0 

409 

269,200 

May 

485,000 

2.940,000 

684,000 

10,000 

662,000 

0 

0 

406 

280.000 

June 

353,000 

2,731.000 

855.000 

11,000 

666.000 

0 

0 

387 

280,000 

July 

316.000 

2,218,000 

941,000 

12.000 

741.000 

0 

0 

354 

280,000 

Aug. 

244.000 

1.581,000 

855.000 

9,000 

806.000 

0 

0 

311 

266,900 

Sept. 

213,000 

961,000 

513,000 

5,000 

513,000 

0 

0 

271 

151.800 

Oct. 

236,000 

656,000 

171,000 

3,000 

171,000 

0 

0 

262 

47,000 

Nov. 

242,000 

718,000 

0 

2,000 

0 

0 

0 

0 

Dec. 

363,000 

958,000 

0 

0 

0 

0 

0 

0 

Total  or 
average 

7,127,000 

4.276,000 

59,000 

5,627,000 

1,798,000 

0 

358 

183  300 

1917 

Jan. 

312.000 

1,321,000 

0 

0 

0 

0 

0 

0 

Feb. 

760.000 

1,633,000 

0 

0 

0 

0 

0 

0 

Mar. 

459,000 

2,393,000 

43,000 

0 

43,000 

0 

0 

400 

17.900 

April 

906,000 

2,809,000 

214,000 

7,000 

537,000 

231,000 

0 

408 

234,400 

May 

580,000 

2,940,000 

684,000 

10,000 

6.'i9.000 

5,000 

0 

409 

280,000 

June 

329,000 

2,821,000 

8.:f,000 

11,000 

660,000 

0 

0 

391 

280.000 

July 

238.000 

2,284,000 

941,000 

12.000 

738.000 

0 

0 

356 

280,000 

.^ug. 

214.000 

1,569.000 

855,000 

9,000 

803.000 

0 

0 

308 

263.400 

Sept. 

185,000 

919,000 

513,000 

5,000 

513,000 

0 

0 

265 

147,600 

Oct. 

200.000 

586,000 

171,000 

3,000 

171,000 

0 

0 

250 

44,600 

Nov. 

224.000 

612,000 

0 

2,000 

0 

0 

0 

0 

Dec. 

298,000 

834,000 

0 

0 

0 

0 

0 

0 

Total  or 

average 

4,705,000 

4,276,000 

59,000 

4,124,000 

236,000 

0 

348 

129,700 

1918 

Jan. 

249,000 

1,132,000 

0 

0 

0 

0 

0 

0 

Feb. 

399,000 

1,381,000 

0 

0 

0 

0 

0 

0 

Mar. 

772,000 

1.780,000 

43,000 

0 

43,000 

0 

0 

372 

16,900 

April 

556,000 

2,509,000 

214,000 

7,000 

214.000 

0 

0 

403 

92.500 

May 

314,000 

2,844,000 

684,000 

10.000 

673,000 

0 

0 

399 

280.000 

June 

232,000 

2.464.000 

855,000 

11.000 

690.000 

0 

0 

369 

280.000 

July 

200,000 

1,830,000 

941,000 

10,000 

806,000 

0 

0 

324 

280,000 

Aug. 

192,000 

1,079,000 

855,000 

7,000 

732,000 

0 

0 

258 

197,400 

Sept. 

186,000 

409,000 

513.000 

3,000 

0 

0 

0 

0 

Oct. 

258,000 

79.000 

171,000 

1,000 

0 

0 

0 

0 

Nov. 

246,000 

165,000 

0 

1,000 

0 

0 

0 

0 

Dec. 
Total  or 

258.000 

410,000 

0 

0 

0 

0 

0 

0 

average 

3.862.000 

4,276.000 

50.000 

3,158,000 

0 

0 

354 

96,400 

1919 

Jan. 

587.000 

668.000 

0 

0 

0 

0 

0 

n 

Feb. 

1.163,000 

1.255,000 

0 

0 

0 

0 

0 

(1 

Mar. 

959,000 

2418,000 

43.000 

0 

340,000 

97,000 

0 

407 

113.100 

April 
May 

752,000 

2,940,000 

214,000 

7,000 

627,000 

118.000 

0 

410 

274.300 

438,000 

2,940,000 

684.000 

10,000 

666,000 

0 

0 

404 

280.000 

June 

252.000 

2,684.000 

855,000 

ll.OOO 

675,000 

0 

0 

381 

280.000 

July 

219.000 

2,070,000 

941,000 

11,000 

766.000 

0 

0 

342 

280.000 

Aug. 

199.000 

1.337.000 

855.000 

8,000 

775.000 

0 

0 

286 

235,500 

Sept. 

168,000 

673.000 

513,000 

4.000 

513,000 

0 

0 

230 

124,600 

Oct. 

203.000 

324.000 

171.000 

2.000 

171.009 

0 

0 

210 

35,600 

Nov. 

186.000 

354,000 

0 

1,000 

0 

0 

0 

0 

Dec. 
Total  or 

180.000 

539,000 

0 

0 

0 

0 

0 

0 

average 

5.306,000 

4,276.000 

54,000 

4,533,000 

215,000 

0 

334 

138,500 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


245 


RESERVOIR  ON  SACRAMENTO  RIVER. 

IRRIGATION  WITH  INCIDENTAL  POWER  GENERATION 


BY  RESERVOIR  OPERATING  DIAGRAM. 
tions  Carried  out  on  a  Dailj'  Basis. 

mary,  see  Table  2,  page  110.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 

Installed  capacity  of  power  plant  400,000  k.v.a.     P.P.  =  0.80. 


:)oordlnated  with  flood  control  by  res 

ervoir  operating  diagram 

Maximum  controlled  £ 

ow  at  Red  Bluff  125.000 

sec.-ft.    Maximum  reservoir  space  required  454,000  ac.-ft. 

Irrigation 

Stage  of 
reservoir 

at 
beginning 

of 

draft  in 
acre-feet 

l^no 
deduction 
for  down- 

Evapora- 
tion in 
acre-feet 

Power 

draft 

through 

turbines 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 

over 

spillway 

in 

Deficiency 

in 

irrigation 

supply 

Average 

power 

head 

through 

period  of 

Average 
power 

j-ield  in 

kilowatts 

(Load 

Year  and 
month 

month  in 
acre-feet 

stream 
prior 

in 
acre-feet 

acre-feet 

in 
acre-feet 

operation 
in  feet 

factor= 
1.00) 

rights) 

1916 

2,138.000 

0 

0 

397.000 

415,000 

0 

0 

386 

160,900 

Jan. 

2.492,000 

0 

0 

646,000 

920,000 

0 

0 

384 

278.500 

Feb. 

2,542,000 

43,000 

0 

616,000 

263,000 

0 

0 

396 

254,300 

Mar. 

2,878,000 

214,000 

7.000 

572,000 

0 

37,000 

0 

410 

251.100 

April 

2,940,000 

684,000 

10,000 

662,000 

0 

0 

0 

406 

280.000 

May 

2,731.000 

8.55,000 

11,000 

666.000 

0 

0 

0 

387 

280,000 

June 

2,218,000 

941.000 

12,000 

741.000 

0 

0 

0 

354 

280,000 

July 

1,581,000 

855,000 

9,000 

806.000 

0 

0 

0 

311 

268.900 

Aug. 

961,000 

513,000 

5,000 

513.000 

0 

0 

0 

271 

151,800 

Sept. 

656,000 

171,000 

3,000 

171,000 

0 

0 

0 

262 

47,000 

Oct. 

718,000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

9i8,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

59,000 

5,790,000 

1,598,000 

37,000 

0 

355 

187,200 

1917 

1,321,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

1,633,000 

0 

0 

0 

0 

0 

0 

0 

Feb. 

2,393,000 

43,000 

0 

43,000 

0 

0 

0 

400 

17,900 

Mar. 

2,809,000 

214,000 

7,000 

537,000 

0 

231,000 

0 

408 

234,400 

April 

2,940,000 

684,000 

10,000 

659.000 

0 

5,000 

0 

409 

280,000 

May 

2,821,000 

855,000 

11,000 

660,000 

0 

0 

0 

391 

280,000 

June 

2,284,000 

941,000 

12.000 

738,000 

0 

0 

0 

356 

280.000 

July 

1,569,000 

855,000 

9,000 

803.000 

0 

0 

0 

308 

263,400 

Aug. 

919,000 

513.000 

5,000 

51.3.000 

0 

0 

0 

265 

147,600 

Sept. 

586,000 

171,000 

3,000 

171,000 

0 

0 

0 

250 

44,600 

Oct. 

012,000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

834,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

59,000 

4,124,000 

236,000 

0 

318 

129,700 

1918 

1,132,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

1,381,000 

0 

0 

0 

0 

0 

0 

0 

Feb. 

1,780,000 

43,000 

0 

43,000 

0 

0 

0 

372 

16,900 

Mar. 

2,509,000 

214,000 

7,000 

214,000 

0 

0 

0 

403 

92,500 

.\pril 

2,844,000 

684,000 

10.000 

673,000 

0 

0 

0 

399 

280,000 

May 

2,464,000 

855,000 

11.000 

690,000 

0 

0 

0 

369 

280,000 

June 

1,830,000 

941.000 

10,000 

806,000 

0 

0 

0 

324 

280,000 

July 

1,079,000 

855,000 

7,000 

732,000 

0 

0 

0 

258 

197,400 

Aug. 

409.000 

513.000 

3,000 

0 

0 

0 

0 

0 

S^pt. 

79,000 

171,000 

1,000 

0 

0 

0 

0 

0 

Oct. 

165,000 

0 

1,000 

0 

0 

0 

0 

0 

Nov. 

410,000 

0 

0 

0 

0 

0 

0 

0 

D-c. 
Total  or 
a/erage 

4,276,000 

50,000 

3,138,000 

0 

0 

0 

354 

96.400 

1919 

668,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

1,255,000 

0 

0 

0 

0 

0 

0 

0 

Feb. 

2.418,000 

43,000 

0 

507,000 

45,000 

0 

0 

398 

209.800 

Mar. 

2,825,000 

214,000 

7,000 

592,000 

3,000 

35,000 

0 

403 

258,600 

April 

2,940,000 

684,000 

10.000 

666,000 

0 

0 

0 

404 

280,000 

May 

2,684,000 

855,000 

11,000 

675,000 

0 

0 

0 

381 

280,000 

June 

2,070,000 

941,000 

11,000 

766,000 

0 

0 

0 

342 

280.000 

July 

1,337,000 

8.55.000 

8,000 

775,000 

0 

0 

0 

286 

235..500 

Aug. 

673,000 

513.000 

4,000 

513,000 

0 

0 

0 

230 

124,600 

Sept. 

324,000 

171,000 

2,000 

171,000 

0 

0 

0 

210 

35,600 

Oct. 

354,000 

0 

1,000 

0 

0 

0 

0 

0 

Nov. 

539,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

54,000 

4,665,000 

48,000 

35,000 

0 

332 

142,900 

24G 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  2a  (Continued).     KENNETT 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet. 

Capacity  of  reservoir  2,940,000  acre-feet. 


Estimated 

Without  flood  control 

Irrigation 

run-off 

Stage  of 

draft  in 

Power 

draft 

through 

turbines 

Deficiency 

Average 

Average 

Year  and 

at  dam 

reservoir 

acre-feet 

Waste 

power 

power 

month 

site  in 

at 

(no 

Evapora- 

over 

in 

irrigation 

supply 

head 

yield  in 

acre-feet 

beginning 

deduction 

tion  in 

spillway 

through 

kilowatts 

of 

for  down- 

acre-feet 

in 

period  of 

(Load 

month  in 
acre-feet 

stream 
prior 
rights) 

in 
acre-feet 

acre-feet 

in 
acre-feet 

operation 
in  feet 

factor= 
1.00) 

1920 

Jan. 

207.000 

719,000 

0 

0 

0 

0 

0 

■    0 

Feb. 

176,000 

926,000 

0 

0 

0 

0 

0 

0 

Mar. 

372.000 

1,102,000 

43,000 

0 

43,000 

0 

0 

318 

14,500 

.\pril 

493.000 

1,431,000 

214,000 

5,000 

214,000 

0 

0 

340 

80.100 

May 

286.000 

1,705,000 

684,000 

7,000 

684,000 

0 

0 

333 

243.300 

.Tune 

216,000 

1,300,000 

855,000 

7,000 

747.000 

0 

0 

285 

233,300 

July 

192.000 

654,000 

841.000 

5,000 

291,000 

0 

100,000 

231 

69,100 

Aug. 

176,000 

0 

176,000 

0 

0 

0 

679,000 

0 

Sept. 

140,000 

0 

140.000 

0 

0 

0 

373,000 

0 

Oct. 

180.000 

0 

168,000 

0 

0 

0 

3,000 

0 

Nov. 

896,000 

12,000 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,121,000 

908,000 

0 

0 

0 

0 

0 

0 

4,45.5,000 

3,121,000 

24,000 

1,979,000 

0 

1,155,000 

315 

53,400 

1921 

Jan. 

1,492,000 

2,029.000 

0 

0 

162,000 

419,000 

0 

402 

67.700 

Feb. 

1.035,000 

2,940,000 

0 

0 

602,000 

433.000 

0 

404 

280,000 

Mar. 

982,000 

2,940,000 

43,000 

0 

660,000 

322,000 

0 

407 

280,000 

April 

559,000 

2,940,000 

214,000 

7,000 

540,000 

12,000 

0 

410 

236,500 

May 

493.000 

2,940,000 

684,000 

10,000 

663,000 

0 

0 

406 

280.000 

June 

316,000 

2,739,000 

855,000 

11,000 

666,000 

0 

0 

387 

280,000 

July 

220,000 

2,189,000 

941,000 

12,000 

7,50,000 

0 

0 

349 

280,000 

Aug. 

192,000 

1,456,000 

855,000 

8,000 

787,000 

0 

0 

298 

249,200 

Sept. 

175,000 

785,000 

513,000 

4,000 

513,000 

0 

0 

247 

136,300 

Oct. 

196,000 

443,000 

171,000 

2,000 

171,000 

0 

0 

229 

40,100 

Nov. 

205,000 

466,000 

0 

2,000 

0 

0 

0 

0 

Dec. 
Total  or 
average 

390,000 

669,000 

0 

0 

0 

0 

0 

0 

6,255,000 

4,276,000 

56,000 

5,514,000 

1,186,000 

0 

350 

176,800 

19J2 

Jan. 

300,000 

1,0.59,000 

0 

0 

0 

0 

0 

0 

Feb. 

679,000 

1,359,000 

0 

0 

0 

0 

0 

0 

Mar. 

567,000 

2,038,000 

43,000 

0 

43,000 

0 

0 

383 

17.300 

April 

604,000 

2,562.000 

214.000 

7,000 

219,000 

0 

0 

410 

95.600 

May 

577,000 

2,940,000 

684,000 

10.000 

060,000 

0 

0 

409 

280,000 

June 

317,000 

2.823,000 

855.000 

11,000 

660,000 

0 

0 

390 

280,000 

July 

203,000 

2,274,000 

941,000 

12,000 

741.000 

0 

0 

354 

280,000 

Aug. 

182,000 

1,524.000 

855,000 

8,000 

794,000 

0 

0 

302 

255,400 

Sept. 

161,000 

843,000 

513.000 

4,000 

513,000 

0 

0 

2^4 

140,400 

Oct. 

208,000 

487,000 

171,000 

2,000 

171,000 

0 

0 

237 

41,800 

Nov. 

244,000 

522,000 

0 

2,000 

0 

0 

0 

0 

Dec. 
Total  or 
average 

462.000 

764,000 

0 

0 

0 

0 

0 

0 

4,504,000 

4,276,000 

56,000 

3.801,000 

0 

0 

342 

116,700 

1923 

Jan. 

467,000 

1,226,000 

0 

0 

0 

0 

0 

0 

Feb. 

297,000 

1,693,000 

0 

0 

0 

0 

0 

0 

Mar. 

287,000 

1,990.000 

43,000 

0 

43,000 

0 

0 

375 

16.900 

April 

632,000 

2,234,000 

214,000 

6,000 

214,000 

0 

0 

393 

90,700 

May 

322.000 

2.M6,(X)0 

684,000 

10.000 

681,000 

0 

0 

389 

278,600 

June 

236,000 

2,274.000 

855,000 

10.000 

708,000 

0 

0 

360 

280,000 

July 

184,000 

1,645.000 

941.000 

10,000 

803,000 

0 

0 

303 

264,300 

Aug. 

165,000 

878.000 

855,000 

6,000 

682,000 

0 

0 

224 

154,200 

Sept. 

157.000 

182,000 

338.000 

1.000 

0 

0 

175,000 

0 

Oct. 

187,000 

0 

171,000 

0 

0 

0 

0 

0 

Nov. 

176,000 

16.000 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

184,000 

192,000 

0 

0 

0 

0 

0 

0 

3,204,000 

4,101,000 

43,000 

3,134,000 

0 

175,000 

341 

91,100 

THE    CONTROL   OP    FLOODS    BY    RESERVOIRS. 


247 


RESERVOIR  ON  SACRAMENTO  RIVER. 

IRRIGATION  WITH  INCIDENTAL  POWER  GENERATION 


BY  RESERVOIR  OPERATING  DIAGRAM. 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  2,  page  110.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 

Installed  capacity  of  power  plant  400,000  k.v.a.     P.P.  =  0.80. 


Coordinated 

with  flood  conlrol  by  res 

srvoir  operating  diagram 

Maximum  controllsd  flow  at  Red  Bluff  125, OOC 

sec.-ft.    M 

aximum  reservoir  space  required  454,000  ac.-ft. 

Irrigation 

Stage  of 
reservoir 

draft  in 
aere-feet 

Power 

draft 

through 

turbines 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 

Deficiency 

Average 
power 

Average 
power 

at 

no) 

Evapora- 

over 

in 

head 

yield  in 

Year  and 

bsginning 
of 

deduction 
for  down- 

tion in 
acre-feet 

spillway 

in 

irrigation 
supply 

through 
period  of 

kilowatts 
(Load 

month 

month  in 
acre-feet 

stream 
prior 

in 
acre-feet 

acre-feet 

in 
acre-feet 

operation 
in  feet 

factor= 
1.00) 

rights) 

1920 

719,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

926,000 

0 

0 

0 

0 

0 

0 

0 

Feb. 

1,102,000 

43,000 

0 

43,000 

0 

0 

0 

318 

14,500 

Mar, 

1.431,000 

214,000 

5,000 

214,000 

0 

0 

0 

340 

80,100 

April 

1,705,000 

684,000 

7,000 

684,000 

0 

0 

0 

333 

243,300 

May 

1,300.000 

855.000 

7,000 

747,000 

0 

0 

0 

285 

233,300- 

June 

654,000 

841,000 

5,000 

291,000 

0 

0 

100,000 

231 

69,100 

July 

0 

176.000 

0 

0 

0 

0 

679,000 

0 

Aug. 

0 

140.000 

0 

0 

0 

0 

373,000 

0 

Sspt. 

0 

168,000 

0 

0 

0 

0 

3,000 

0 

Oct. 

12,000 

0 

0 

0 

0 

0 

0 

0 

Nov. 

908,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

3,121,000 

24,000 

1,979,000 

0 

0 

1,155,000 

315 

53,400 

1921 

2.029,000 

0 

0 

331,000 

537,000 

0 

0 

388 

134,700 

Jan. 

2,653,000 

0 

0 

618,000 

508.000 

0 

0 

,389 

280,000 

Feb. 

2,562,000 

43,000 

0 

675,000 

47,000 

0 

0 

397 

280,000 

Mar. 

2,822,000 

214,000 

7,000 

4,34,000 

0 

0 

0 

411 

190,600 

Aoril 

2,940,000 

684.000 

10,000 

663,000 

0 

0 

0 

406 

280,000 

May 

2,739,000 

855,000 

11.000 

666.000 

0 

0 

0 

387 

280,000 

June 

2,189,000 

941.000 

12,000 

750,000 

0 

0 

0 

349 

280,000 

July 

1,456,000 

855,000 

8,000 

787  000 

0 

0 

0 

298 

219,200 

Aug. 

785,000 

513,000 

4,000 

513,000 

0 

0 

0 

247 

136,300 

S^pt. 

443,000 

171,000 

2.000 

171,000 

0 

0 

0 

229 

40,100 

Oct. 

466.000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

669,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

4,276,000 

56,000 

5,608,000 

1,092,000 

0 

0 

348 

178,700 

1922 

1,059,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

1,359,000 

0 

0 

0 

0 

0 

0 

0 

Feb. 

2,038,000 

43,000 

0 

43,000 

0 

0 

0 

383 

17,300 

Mar. 

2,562,000 

214,000 

7,000 

219,000 

0 

0 

0 

410 

95,600 

.April 

2,940,000 

684,000 

10.000 

660.000 

0 

0 

0 

403 

280,000 

May 

2.823,000 

855,000 

11,000 

660,000 

0 

0 

0 

390 

280,000 

June 

2,274.000 

941,000 

12,000 

741,000 

0 

0 

0 

354 

280.000 

July 

1,524,000 

855,000 

8,000 

794.000 

0 

0 

0 

302 

2,55,400 

Aug. 

843,000 

513,000 

4.000 

513,000 

0 

0 

0 

254 

140,400 

Sjpt. 

487,000 

171,000 

2,000 

171,000 

0 

0 

0 

237 

41,800 

Oct. 

522.000 

0 

2,000 

0 

0 

0 

0 

0 

Nov. 

764,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

56,000 

3.801,000 

0 

0 

0 

342 

116,700 

1923 

1,226,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

1,693.000 

0 

0 

0 

0 

0 

0 

0 

Feb. 

1,990,000 

43.000 

0 

43,000 

0 

0 

0 

37.5 

16,900 

Mar. 

2,234,000 

214,000 

6,000 

214,000 

0 

0 

0 

393 

90,700 

April 

2,646,000 

684,000 

10,000 

684,000 

0 

0 

0 

389 

278,600 

May 

2.274,000 

855,000 

10,000 

708.000 

0 

0 

0 

360 

280.000 

June 

1,645.000 

941.000 

10,000 

803,000 

0 

0 

0 

309 

264,300 

July 

878,000 

855.000 

6,000 

682,000 

0 

0 

0 

224 

151.200 

Aug. 

182,000 

338,000 

1,000 

0 

0 

0 

175,000 

0 

S^pt. 

0 

171,000 

0 

0 

0 

0 

0 

0 

Oct. 

16,000 

0 

0 

0 

0 

0 

0 

0 

Nov. 

192,000 

0 

0 

0 

0 

0 

0 

0 

DiC. 
Total  or 
average 

4,101,000 

43,000 

3,134,000 

0 

0 

175,000 

341 

91,100 

248 


WATER  RESOURCES  OF    CALIFORNIA 


TABLE  2a  (Concluded).     KENNETT 

WATER  AND  POWER  YIELD,  OPERATING  PRIMARILY  FOR 

BOTH 
WITH  AND  WITHOUT  FLOOD  CONTROL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet. 

Capacity  of  reservoir  2,940,000  acre-feet. 


Estimated 

Without  flood  control 

Irrigation 

run-off 

Stage  of 

draft  in 

Power 

draft 

through 

turbines 

Deficiency 

.\verage 

Average 

Year  and 

at  dam 

reservoir 

acre-feet 

Waste 

power 

power 

month 

site  in 

at 

(no 

Evapora- 

over 

lit 

irrigation 

supply 

head 

yield  in 

acre-feet 

beginning 
of 

deduction 
for  down- 

tion in 
acre-feet 

spillway 
in 

through 
period  of 

kilowatts 
(Load 

month  in 
acre-feet 

stream 
prior 
rights) 

in 
acre-feet 

acre-feet 

in 
acre-feet 

operation 
in  feet 

factor= 
1.00) 

1924 

Jan. 

203,000 

376,000 

0 

0 

0 

0 

0 

0 

Feb. 

332,000 

579,000 

0 

0 

0 

0 

0 

0 

Mar. 

200,000 

911,000 

43,000 

0 

43,000 

0 

0 

295 

13.400 

April 

.    176,000 

1,068,000 

214,000 

4,000 

214,000 

0 

0 

301 

70,700 

May 

1.55.000 

1,020,000 

684,000 

5,000 

684,000 

0 

0 

265 

191,400 

June 

141,000 

492,000 

629,000 

4,000 

131,000 

0 

226.000 

220 

30,000 

July 

140.000 

0 

140,000 

0 

0 

0 

801.000 

0 

Aug. 

140,000 

0 

140.000 

0 

0 

0 

715,000 

0 

Sept. 

128,000 

0 

128.000 

0 

0 

0 

385.000 

0 

Oct. 

178,000 

0 

158,000 

0 

0 

0 

13,000 

0 

Nov. 

317,000 

20,000 

0 

0 

0 

0 

0 

0 

Dec. 

321,000 

337,000 

0 

0 

0 

0 

0 

0 

Total  or 
average 

2,431,000 

2,136,000 

13,000 

1,072,000 

0 

2,140,000 

283 

25,600 

1925 

Jan. 

301,000 

658,000 

0 

0 

0 

0 

0 

0 

Feb. 

1,769,000 

959,000 

0 

0 

0 

0 

0 

0 

Mar. 

563,000 

2,728,000 

43.000 

0 

338,000 

13,000 

0 

4ii 

143,800 

April 

026,000 

2,940,000 

214.000 

7,000 

635,000 

284,000 

0 

408 

277,500 

May 

474,000 

2,940,000 

684,0(10 

10,000 

663,000 

0 

0 

405 

280,000 

June 

276.000 

2,720,000 

8.55.000 

11,000 

669.000 

0 

0 

384 

280,000 

July 

173,000 

2,130,000 

941.000 

11.000 

763.000 

0 

0 

394 

280,000 

Aug. 

167,000 

1,351,000 

855.000 

8,000 

772.000 

0 

0 

286 

234,100 

Sept. 

163,000 

655,000 

513.000 

4,000 

513,000 

0 

0 

227 

122,400 

Oct. 

181,000 

301.000 

171.000 

2,000 

0 

0 

0 

0 

Nov. 

1!)2,000 

309.000 

0 

1,000 

0 

0 

0 

0 

Dec. 

235.000 

500,000 

0 

0 

0 

0 

0 

0 

Total  or 
average 

5,420,000 

4,276,000 

54,000 

4.353,000 

297,000 

0 

352 

135,500 

Total  for 

30-year 

period. 

1896-1926 

188,012,000 

124.570,000 

1,641,000 

i36,ioaooo 

33,096.000 

3,710,000 

Average 

for 

30-year 

period, 

1896-1926 

6,267,000 

4,152,000 

55,000 

4,537,000 

1,103,000 

124,000 

353.4 

145.300 

THE   CONTROL   OF   FLOODS  BY   RESERVOIRS. 


249 


RESERVOIR  ON  SACRAMENTO  RIVER. 

IRRIGATION  WITH  INCIDENTAL  POWER  GENERATION 


BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  2,  page  1 10.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 

Installed  capacity  of  power  plant  400,000  k.v.a.     P.P.  =  0.80. 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125,0OC 

S8C.-ft.      M 

iximum  reservoir  space  required  454,000  ac.-it. 

Irrigation 

Stage  of 
reservoir 

at 

beginning 

of 

draft  in 
acre-feet 

(no 
deduction 
for  down- 

Evapora- 
tion in 
acre-feet 

Power 

draft 

tlirough 

turbines 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 

over 

spillway 

in 

Deficiency 

in 

irrigation 

supply 

Average 

power 

head 

through 

period  of 

Average 
power 

yield  in 

kilowatts 

(Load 

Year  and 
month 

month  in 
acre-feet 

stream 
prior 

in 
acre-feet 

acre-feet 

in 
acre-feet 

operation 
in  feet 

factor= 
1.00) 

rights) 

1924 

376,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

579,000 

0 

0 

0 

0 

0 

0 

0 

Feb. 

911,000 

43,000 

0 

43,000 

0 

0 

0 

29.5 

13,400 

Mar. 

1,068,000 

214,000 

4,000 

214,000 

0 

0 

0 

301 

70,700 

April 

1,026,000 

684,000 

5.000 

684.000 

0 

0 

0 

265 

191,400 

May 

492,000 

629,000 

4,000 

131,000 

0 

0 

226,000 

220 

30,000 

June 

0 

140,000 

0 

0 

0 

0 

801,000 

0 

July 

0 

140,000 

0 

0 

0 

0 

715,000 

0 

Aug. 

0 

128,000 

0 

0 

0 

0 

385,000 

0 

Sept. 

0 

158,000 

0 

0 

0 

0 

13,000 

0 

Oct. 

20,000 

0 

0 

0 

0 

0 

0 

0 

Nov. 

337,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

2,136,000 

13,000 

1,072,000 

0 

0 

2,140.000 

283 

25,600 

1925 

658,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

959,000 

0 

0 

111,000 

89,000 

0 

0 

387 

49,900 
98,8(ro 

Feb. 

2,528,000 

43,000 

0 

239,000 

36,000 

0 

0 

401 

Mar. 

2,816,000 

214,000 

7,000 

588,000 

27,000 

180,000 

0 

408 

256,900 

April 

2,940,000 

684,000 

10,000 

663,000 

0 

0 

0 

405 

280,000 

May 

.2,720,000 

855,000 

11,000 

669,000 

0 

0 

0 

384 

280,000 

June 

2,130,000 

941,000 

11,000 

763,000 

0 

0 

0 

344 

280,000 

July 

1,351,000 

855,000 

8,000 

772,000 

0 

0 

0 

286 

234,100 

Aug. 

655,000 

513,000 

4,000 

513,000 

0 

0 

0 

227 

122,400 

Sept. 

301,000 

171,000 

2,000 

0 

0 

0 

0 

0 

Oct. 

309,000 

0 

1,000 

0 

0 

0 

0 

0 

Nov. 

500,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

54,000 

4,318,000 

152,000 

180,000 

0 

352 

133,900 

Total  for 

30-year 

period, 

124,570,000 

1,641,000 

136,982,000 

26,574,000 

5,642,000 

3.710,000 

1896-1926 

Average 
for 

30-year 
period. 

4,152,000 

55,000 

4  566,000 

886,000 

188,000 

124,000 

352.9 

145.60. 

1896-1926 

IG— 52411 


250 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  3a.     KENNETT  RESER 

COMPARISON  OF  WATER  YIELD 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dami  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Year  and 
month 


Estimated 

run-off  at 

dam  site  in 

acre-feet 


Flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 
Maximum  reservoir  space  required  454,000  ac.-ft. 


Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 


Irrigation 

draft  in 

acre-feet 

(no  deduction 

for  down- 
stream prior 
rights) 


Evaporation 
in  acre-feet 


Release 

through  flood 

control  outlets 

in  acre-feet 


Waste  over 

spillway  in 

acre-feet 


1896 

Jan. 

Feb. 

Mar. 

April 

May 

.June 

July 

Aug. 

Sept. 

Oct. 

Nov. 

Dec. 
Total  or 
average 

1897 

Jan. 

Feb. 

Mar. 

April 

May 

June 

July 

Aug. 

Sept. 

Oct. 

Nov. 

Dec. 
Total  or 
average 

1898 

Jan. 
Feb. 
Mar. 
April 
May 
June 
July 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
Total  or 
average 

1899 

Jan. 
Feb. 
Mar. 
April 
May 
Juno 
July 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
Total  or 
average 


1,980,000 
474,000 
738,000 
891,000 

1,194,000 
536,000 
313,000 
268,000 
258,000 
262,000 
472,000 
920,000 


1,306,000 


.^77,000 
1,338.000 
737.000 
858,000 
.554,000 
310,000 
275,000 
254,000 
247,000 
262,000 
274,000 
366,000 

6,052,000 


257,000 
478,000 
380,000 
274,000 
300,000 
304,000 
2o7,000 
22.7.000 
198,000 
221,000 
217,000 
217,000 


3,308,000 


605,000 
253,000 
1100,000 
456,000 
33(),0()() 
302, (H)0 
240,(K)0 
224,000 
197,000 
252  000 
645,000 
646.000 


5,050,000 


1,860,000 
2,509,000 
2,719,000 
2,940,000 
2,940,000 
2,940,000 
2,609,000 
1,968,000 
1,371,000 
1,110,000 
1,197,000 
1,666,000 


0 

0 

43,000 

214,000 

684,000 

855.000 

941.000 

855,000 

513,000 

171,000 

0 

0 


0 

0 

0 

7,000 

10.000 

12,000 

13,000 

10,000 

6,000 

4,000 

3,000 

0 


1,331,000 
264,000 
172,000 
0 
0 
0 
0 
0 
0 
0 
0 
0 


0 

0 

302,000 

670,000 

£00,000 

0 

0 

0 

0 

0 

0 

0 


2,586,000 

2,508,000 

2.530,000 

2  811,000 

2,940,000 

2,797,000 

2,241,000 

1,. 563, 000 

953,000 

682,000 

770,000 

1,042,000 


4,276,000 


0 

0 

43,000 

214,000 

684,000 

855,000 

941.000 

855,000 

£13,000 

171,000 

0 

0 


65,000 


0 

0 

0 

7,000 

10,000 

11,000 

12,000 

9.000 

5,000 

3,000 

2,000 

0 


1,767,000 


655,000 
l,3ie,000 

413.000 
29,000 
0 
0 
0 
0 
0 
0 
0 
0 


1,472,000 


0 
0 
0 
479,000 
3,000 
0 
0 
0 
0 
0 
0 
0 


1,408,000 

1.665,000 

2,143,000 

2,480,000 

2,533,000 

2,140,000 

1,579,000 

866.000 

230,000 

0 

50,000 

267,000 


484,000 
1,089.000 
1,342,000 
2.199,000 
2.435,000 
2.072,000 
1.510.000 

800.000 

164,000 

0 

81,000 

726,000 


4,276,000 


0 

0 

43,000 

214,000 

684,000 

855,000 

941,000 

855.000 

426,000 

171,000 

0 

0 


4,189,000 


0 

0 

43,000 

214,000 

084,000 

855,000 

941,000 

855,000 

360,000 

171,000 

0 

0 


4,123,000 


59,000 


0 

0 

0 

7,000 

9,000 

10.000 

9,000 

6.000 

2,000 

0 

0 

0 


43,000 


0 

0 

0 

6,000 

9,000 

9,000 

9,000 

5.000 

1,000 

0 

0 

0 


39,000 


2.413,000 


482000 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


251 


VOIR  ON  SACRAMENTO  RIVER. 
OPERATING  PRIMARILY  FOR  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  3,  page  1 12.) 

Seasonal  irrgation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 


Flood  control,  holding  maximum  reservoir  space  required  (454,000  ac.-ft.) 

in  reserve  throughout  flood  season 

Maximum  controlled  flow 

at- Red  Bluff  125,000  sec.-ft. 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Irrigation 

draft  in 

acre-feet 

Cno  deduction 

for  down- 
stream prior 
rights) 

Evaporation 
in  acre-feet 

Release 

through  flood 

control  outlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

in  irrigation 

supply  in 

acre-feet 

Year  and 
month 

1896 

1,860,000 

0 

0 

1,354,000 

0 

0 

Jan. 

2,486,000 

0 

0 

474,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

695,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

137.000 

79,000 

0 

April 

2,940,000 

684,000 

10.000 

0 

500.000 

0 

May 

2,940,000 

855,000 

12,000 

0 

0 

0 

June 

2,609,000 

941,000 

13.000 

0 

0 

0 

July 

1,968,000 

855,000 

10,000 

0 

0 

0 

Aug. 

1,371,000 

513,000 

6,000 

0 

0 

0 

Sept. 

1,110,000 

171,000 

4,000 

0 

0 

0 

Oct. 

1,197,000 

0 

3,000 

0 

0 

0 

Nov. 

1,666,000 

0 

0 

100,000 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

65,000 

2,760,000 

579.000 

0 

1897 

2,488,000 

0 

0 

577,000 

0 

0 

Jan. 

i          2,486,000 

0 

0 

1,338,000 

0 

0 

Feb. 

■          2,486,000 

43,000 

0 

694,000 

0 

0 

Mar. 

B.         2,486,000 

214,000 

7,000 

138,000 

45.000 

0 

April 

■          2,940,000 

684,000 

10,000 

0 

3,000 

0 

May 

1          2,797,000 

855,000 

11,000 

0 

0 

0 

June 

2,241,000 

941,000 

12,000 

0 

0 

0 

July 

1,563,000 

855,000 

9,000 

0 

0 

0 

Aug. 

953,000 

513,000 

5,000 

0 

0 

0 

Sept. 

682,000 

171,000 

3,000 

0 

0 

0 

Oct. 

770,000 

0 

2,000 

0 

0 

0 

Nov. 

1,042,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

59,000 

2,747.000 

48,000 

0 

1898 

1,408,000 

0 

0 

0 

0 

0 

Jan. 

1,665,000 

0 

0 

0 

0 

0 

Feb. 

2,143,000 

43,000 

0 

0 

0 

0 

Mar. 

:           2,180,000 

214,000 

7,000 

5,000 

0 

0 

April 

■          2,528,000 

684,000 

9,000 

0 

0 

0 

May 

T         2,135,000 

855,000 

10,000 

0 

0 

0 

June 

1,574,000 

941,000 

9,000 

0 

0 

0 

July 

861,000 

855,000 

6,000 

0 

0 

0 

Aug. 

225,000 

421,000 

2,000 

0 

0 

92,000 

Sept. 

1                       0 

171,000 

0 

0 

0 

0 

Oct. 

■             50,000 

0 

0 

0 

0 

0 

Nov. 

^          267,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4.184,000 

43,000 

5.000 

0 

92,000 

1899 

484,000 

0 

0 

0 

0 

0 

Jan. 

1,089,000 

0 

0 

0 

0 

0 

Feb. 

1,342,000 

43,000 

0 

0 

0 

0 

Mar. 

2,199,000 

214,000 

6,000 

0 

0 

0 

April 

2,435.000 

684,000 

9,000 

0 

0 

0 

May 

2,072,000 

855,000 

9,000 

0 

0 

0 

June 

1,510,000 

941,000 

9,000 

0 

0 

0 

July 

800,000 

855,000 

5,000 

0 

0 

0 

Aug. 

164.000 

360,000 

1.000 

0 

0 

153,000 

Sept. 

0 

171,000 

0 

0 

0 

0 

Oct. 

81,000 

0 

0 

0 

0 

0 

Nov. 

726,000 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

4,123,000 

39,000 

0 

0 

153.000 

252 


WATER   RESOURCES  OP    CALIFORNIA. 


TABLE  3a  (Continued).     KENNETT 

COMPARISON  OF  WATER  YIELD 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Re<l  Bluff  125 

000  sec.-ft. 

Maximum  reservoir  space  required  454,000  ac.-ft. 

Estimated 

Year  and 
month 

run-off  at 

dam  site  in 

acre-feet 

Stage  of 
reservoir  at 
beginning 
of  month  in 

acre-feet 

Irrigation 

draft  in 

aere-feet 

(no  deduction 

for  down- 
stream prior 
rights) 

Evaporation 
in  acre-feet 

Release 

through  flood 

control  outlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

in  irrigation 

supply  in 

acre-feet 

1900 

Jan. 

1,299,000 

1.372,000 

0 

0 

181.000 

0 

0 

Feb. 

391.000 

2,490,000 

0 

0 

302,000 

0 

0 

Mar. 

912,000 

2,579.000 

43,000 

0 

570,000 

0 

0 

April 

457,000 

2,878,000 

214,000 

7.000 

0 

174.000 

0 

May 

413,000 

2,940,000 

684,000 

10,000 

0 

0 

0 

June 

247,000 

2,659,000 

855.000 

11,000 

0 

0 

0 

July 

219,000 

2,040,000 

941.000 

11,000 

0 

0 

0 

Aug. 

208,000 

1,307,000 

855.000 

8.000 

0 

0 

0 

Sept. 

201.000 

652,000 

513.000 

4,000 

0 

0 

0 

Oct. 

308,000 

336,000 

171,000 

2,000 

0 

0 

0 

Nov. 

368,000 

471,000 

0 

2,000 

0 

0 

0 

Dec. 

697,000 

837,000 

0 

0 

0 

0 

0 

Total  or 
average 

5,720,000 

4.276,000 

55,000 

1,053,000 

174,000 

0 

1901 

Jan. 

895,000 

1,534,000 

0 

0 

0 

0 

0 

Feb. 

1,304,000 

2,429,000 

0 

0 

1,192,000 

0 

0 

Mar. 

749,000 

2,541,000 

43,000 

0 

443,000 

0 

0 

April 

382.000 

2,804,000 

214,000 

7,000 

0 

25,000 

0 

May 

411,000 

2,940,000 

684,000 

10.000 

0 

0 

0 

June 

240,000 

2,657,000 

855,000 

11.000 

0 

0 

0 

July 

218,000 

2,031,000 

941,000 

11,000 

0 

0 

0 

Aug. 

206.000 

1,297,000 

855,000 

8,000 

0 

0 

0 

Sept. 

200.000 

640,000 

513,000 

4,000 

0 

0 

0 

Oct. 

215,000 

323,000 

171,000 

2,000 

0 

0 

0 

Nov. 

354,000 

365,000 

0 

1,000 

0 

0 

0 

Dec. 
Total  or 
average 

550,000 

718,000 

0 

0 

0 

0 

0 

5,724,000 

4,276,000 

54,000 

1,635,000 

25,000 

0 

1902 

Jan. 

227,000 

1,268,000 

0 

0 

0 

0 

0 

Feb. 

2,782,000 

1,495,000 

0 

0 

1.711.000 

0 

0 

Mar. 

1,115,000 

2,566,000 

43.000 

0 

796.000 

0 

0 

April 

891,000 

2,842.000 

214,000 

7,000 

0 

572,000 

0 

May 

765,000 

2,940,000 

684,000 

10,000 

0 

105,000 

0 

June 

407,000 

2,906,000 

855,000 

12,000 

0 

0 

0 

July 

254,000 

2,446,000 

Ot  1.000 

13,000 

0 

0 

0 

Aug. 

234,000 

1,746,000 

855,000 

9,000 

0 

0 

0 

Sept. 

184,000 

1,116,000 

513,000 

5.000 

0 

0 

0 

Oct. 

235,000 

782,000 

171.000 

3,000 

0 

0 

0 

Nov. 

829,000 

843,000 

0 

2,000 

0 

0 

0 

Dec. 

762,000 

1,670,000 

0 

0 

0 

0 

0 

Total  or 
average 

8,685,000 

4,276.000 

01.000 

2.507.000 

677,000 

0 

1903 

Jan. 

1,113,000 

2.432,000 

0 

0 

1,056,000 

0 

0 

Feb. 

633,000 

2,489,000 

0 

0 

574,000 

0 

0 

Mar. 

1,339,000 

2,548.000 

43.000 

0 

1,032,000 

0 

0 

April 
May 

765,000 

2,812,000 

214,000 

7.000 

111.000 

305,000 

0 

458,000 

2.940,000 

684,000 

10.000 

0 

0 

0 

Juno 

278.000 

2.704,000 

855,000 

11.000 

0 

0 

0 

July 

231,000 

2,116.000 

941,000 

11,000 

0 

0 

0 

Aug. 

204,000 

1.395,000 

855,000 

8.000 

0 

0 

0 

Sept. 

174,000 

736,000 

513,000 

4.000 

0 

0 

0 

Oct. 

199,000 

393,000 

171.000 

2.000 

0 

0 

0 

Nov. 

924,000 

419,000 

0 

1.000 

0 

0 

0 

Dec. 

630,000 

1.342.000 

0 

0 

0 

0 

0 

Totol  or 

average 

6.848.000 

4.276.000 

54.000 

2.773.000 

305,000 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


253 


RESERVOIR  ON  SACRAMENTO  RIVER. 
OPERATING  PRIMARILY  FOR  IRRIGATION 

FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  3,  page  1 12.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 


Flood  control,  holding  maximum  reservoir  space  required  (451,000  ac.-ft.) 

in  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Stage  of 
reservoir  at 
beginning 
of  month  in 

acre-feet 

Irrigation 

draft  in 

acre-feet 

(no  deduction 

for  down- 
stream prior 
rights) 

Evaporation 
in  acre-feet 

Release 

through  flood 

control  outlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

in  irrigation 

supply  in 

acre-feet 

Year  and 
month 

1900 

1,372,000 

0 

0 

185,000 

0 

0 

Jan. 

2,486,000 

0 

0 

391,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

869,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

61,000 

0 

0 

April 

2,661,000 

684,000 

10,000 

0 

0 

0 

May 

2,380,000 

855,000 

10,000 

0. 

0 

0 

June 

1,762,000 

941,000 

10,000 

0 

0 

0 

July 

£           1,030,000 

855,000 

6,000 

0 

0 

0 

Aug. 

■             377,000 

513,000 

3,000 

0 

0 

0 

Sept. 

^               62,000 

171,000 

0 

0 

0 

0 

Oct. 

199,000 

0 

1,000 

0 

0 

0 

Nov. 

566,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1 

4,276,000 

47,000 

1,506,000 

0 

0 

1901 

1,263,000 

0 

0 

0 

0 

0 

Jan. 

2,158,000 

0 

0 

976,000 

0 

0 

Feb. 

2,486  000 

43,000 

0 

706,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

45,0f0 

0 

0 

April 

2,602,000 

684,000 

9,000 

0 

0 

0 

May 

2,320,000 

855,000 

10,000 

0 

0 

0 

June 

1,695,000 

941,000 

10,000 

0 

0 

0 

July 

962,000 

855,000 

6,000 

0 

0 

0 

Aug. 

307,000 

505.000 

2,000 

0 

0 

8,003 

Sept. 

0 

171,000 

0 

0 

0 

0 

Oct. 

44,000 

0 

0 

0 

0 

0 

Nov. 

398,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,268,000 

44,000 

1,727,000 

0 

8,000 

1902 

948,000 

0 

0 

0 

0 

0 

Jan. 

1,175,000 

0 

0 

1,471,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

1,072,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

162,000 

54,000 

0 

April 

2,940,000 

684,000 

10,000 

0 

105,000 

0 

May 

2,906,000 

855,000 

12,000 

0 

0 

0 

June 

2,446,000 

941,000 

13,000 

0 

0 

0 

July 

1,746,000 

855,000 

9,000 

0 

0 

0 

Aug. 

1,116,000 

513,000 

5,000 

0 

0 

0 

Sept. 

782,000 

171,000 

3,000 

0 

0 

0 

Oct. 

843,000 

0 

2,000 

0 

0 

0 

Nov. 

1,670,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

61,000 

2,705,000 

159,000 

0 

1903 

2,432,000 

0 

0 

1,059,000 

0 

0 

Jan. 

2,486,000 

0 

0 

633,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

1,296,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

218,000 

0 

0 

April 

2,812,000 

684,000 

10,000 

0 

0 

0 

May 

2,576,000 

855,000 

11,000 

0 

0 

0 

June 

1,988,000 

941,000 

11,000 

0 

0 

0 

July 

1,267,000 

855,000 

7,000 

0 

0 

0 

Aug. 

609,000 

513,000 

4,000 

0 

0 

0 

Sept. 

266,000 

171,000 

2,000 

0 

0 

0 

Oct. 

292,000 

0 

1,000 

0 

0 

0 

Nov. 

1,215,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

53,000 

3,206,000 

0 

0 

254 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  3a  (Continued).     KENNETT 

COMPARISON  OF  WATER  YIELD 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125, 

000  sec.-ft. 

Maximum  rfcser\-oir  space  required  454,000  ac.-ft. 

Estimated 

Tear  and 
month 

run-off  at 

Irrigation 

dam  site  in 
acre-feet 

Stage  of 
reservoir  at 

banning 
of  month  in 

draft  in 

acre-feet 

(no  deduction 

for  down- 

Evaporation 
in  acre-feet 

Release 

through  flood 

control  outlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

in  irrigation 

supply  in 

acre-feet 

acre-feet 

stream  prior 
rights) 

1904 

Jan. 

473,000 

1,872,000 

0 

0 

0 

0 

0 

Feb. 

1,742.000 

2,345,000 

0 

0 

1,557.000 

0 

0 

Mar. 

2.877,000 

2,530,000 

43,000 

0 

2.506,000 

0 

0 

April 

1.467.000 

2,858,000 

214.000 

7,000 

201.000 

963,000 

0 

May 

914.000 

2,940,000 

684.000 

10,000 

0 

220,000 

0 

June 

505.000 

2.940.000 

855.000 

12,000 

0 

0 

0 

July 

377,000 

2.578.000 

941.000 

13,000 

0 

0 

0 

Aug. 

282,000 

2.001.000 

855.000 

10,000 

0 

0 

0 

Sept. 

271.000 

1.418,000 

513.000 

6,000 

0 

0 

0 

Oct. 

491,000 

1.170.000 

171,000 

4.000 

0 

0 

0 

Nov. 

379.000 

1.486.000 

0 

3,000 

0 

0 

0 

Dec. 

600,000 

1.862.000 

0 

0 

0 

0 

0 

Total  or 

average 

10,378,000 

4,276.000 

65,000 

4,264,000 

1,183,000 

0 

1905 

Jan. 

1,371,000 

2,462,000 

0 

0 

1,201,000 

0 

0 

Feb. 

1,027.000 

2,632,000 

0 

0 

1,060.000 

0 

0 

Mar. 

1,335,000 

2,599,000 

43.000 

0 

970.000 

0 

0 

April 

753,000 

2.921.000 

214.000 

7,000 

47,000 

466,000 

0 

May 

560,000 

2.940,000 

684.000 

10.000 

0 

0 

0 

June 

365,000 

2.806,000 

855,000 

11.000 

0 

0 

0 

July 

269,000 

2.305,000 

941.000 

12,000 

0 

0 

0 

Aug. 

236.000 

1,621,000 

855.000 

9,000 

0 

0 

0 

Sept. 

208,000 

993,000 

513.000 

5,000 

0 

0 

0 

Oct. 

221,000 

683.000 

171,000 

3.000 

0 

0 

0 

Nov. 

229,000 

730.000 

0 

2,000 

0 

0 

0 

Dec. 
Totol  or 
average 

249,000 

957.000 

0 

0 

0 

0 

0 

6,823,000 

4,276,000 

59.000 

3,278,000 

466,000 

0 

1906 

Jan. 

851,000 

1.206.000 

0 

0 

0 

0 

0 

Feb. 

872,000 

2.057,000 

0 

0 

323,000 

0 

0 

Mar. 

1.646.000 

2,606,000 

43.000 

0 

1,374,000 

0 

0 

April 
May 

995,000 
817,000 

2,835,000 
2,940,000 

214.000 
684.000 

7,000 
10,000 

190,000 
0 

479.000 
123.000 

0 
0 

June 

756.000 

2,940.000 

85f.000 

12,000 

0 

44,000 

% 

July 

362.000 

2.785.000 

941.000 

14,000 

0 

0 

1 

Aug. 

280,000 

2.192.000 

855.000 

11,000 

0 

0 

f 

Sept. 

247,000 

1.606.000 

513.000 

7,000 

0 

0 

6 

Oct. 

251,000 

1.333.000 

171,000 

5.000 

0 

0 

0 

Nov. 

256,000 

1.408,000 

0 

3.000 

0 

0 

0 

Dec 

648,000 

1,661,000 

0 

0 

0 

0 

0 

Total  or 
average 

7.981,000 

4,276.000 

69.000 

1,887.000 

646,000 

0 

1907 

Jan. 

936.000 

2.309.000 

0 

0 

757.000 

0 

0 

Feb. 

1,636,000 
2,115,000 

2,488.000 

0 

0 

1.594.000 

0 

0 

Mar. 

2.530.000 

43.000 

0 

1.784.000 

0 

0 

April 
May 

1,250.000 

2.818.000 

214,000 

7.000 

250.000 

657,000 

0 

646.000 

•?.940.000 

684,000 

10.000 

0 

8.000 

0 

Jane 

421.000 

2.884.000 

855,000 

12.000 

0 

0 

0 

July 

334.000 

2.438.000 

941.000 

13.000 

0 

0 

0 

Aug. 

291,000 

1.818.000 

855.000 

10.000 

0 

0 

0 

Sept 

252,000 

1.244.000 

513.000 

6,000 

0 

0 

0 

Cct. 

261,000 

977.000 

171,000 

4,000 

0 

0 

0 

Not. 

256,000 

1.063.000 

0 

3.000 

0 

0 

0 

Dee. 

479.000 

1,316,000 

0 

0 

0 

0 

0 

Total  or 
average 

8,877,000 

4,276.000 

65,000 

4,385,000 

665,000 

0 

THE    CONTROL   OF    FLOODS   BY    RESERVOIRS. 


255 


RESERVOIR  ON  SACRAMENTO  RIVER. 
OPERATING  PRIMARILY  FOR  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  3,  page  112.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 


Flood  control,  hold 

ng  maximum  reservoir  space  required  (454,000  ac.-ft.) 

In  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Red  Bluflf  125,000  sec.-ft. 

Irrigation 

Year  and 

Stage  of 
reser\'oir  at 

beginning 
of  month  in 

acre-feet 

draft  in 

acre-feet 

(no  deduction) 

for  down- 
stream prior 
rights) 

Evaporation 
in  acre-feet 

Release 

through  flood 

control  outlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

in  irrigation 

supply  in 

acre-feet 

menth 

1904 

1,745,000 

0 

0 

0 

0 

0 

Jan. 

2,218,000 

0 

0 

1,474,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

2,8.34,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

326,000 

466,000 

0 

April 

2,940,000 

684,000 

10,000 

0 

220,000 

0 

May 

2.940,000 

855,000 

12,000 

0 

0 

0 

June 

2.578,000 

941,000 

13,000 

0 

0 

0 

July 

2,001,000 

855,000 

10,000 

0 

0 

0 

Aug. 

1.418,000 

513,000 

6,000 

0 

0 

0 

Sept. 

1,170,000 

171,000 

4,000 

0 

0 

0 

Oct. 

1,486,000 

0 

3,000 

0 

0 

0 

Nov. 

1,862,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 

4,276,000 

65,000 

4,634,000 

686,000 

0 

average 
1905 

2,462,000 

0 

0 

1,347,000 

0 

0 

Jan. 

2,486,000 

0 

0 

1,027,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

1,292,000 

0 

0 

Mar. 

2.486,000 

214,000 

7,000 

196,000 

0 

0 

April 

2,822,000 

684,000 

10,000 

0 

0 

0 

May 

2,688,000 

855,000 

11,000 

0 

0 

0 

June 

2,187.000 

941,000 

12,000 

0 

0 

0 

July 

1,503,000 

855,000 

8,000 

0 

0 

0 

Aug. 

876,000 

513,000 

4,000 

0 

0 

0 

Sept. 

567,000 

171,000 

3,000 

0 

0 

0 

Oct. 

614,000 

0 

2,000 

0 

0 

0 

Nov. 

841,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 

4,276,000 

57,000 

3,862,000 

0 

0 

average 
1906 

1,090,000 

0 

0 

0 

0 

0 

Jan. 

1,941,000 

0 

0 

327,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

1,579,000 

0 

0 

Mar. 

2,510,000 

214,000 

7,000 

347,000 

0 

0 

April 

2,937,000 

684,000 

10,000 

0 

120,000 

0 

May 

2,940,000 

855,000 

12,000 

0 

44,000 

0 

June 

2,785,000 

941,000 

14,000 

0 

0 

0 

July 

2,192,000 

855,000 

11,000 

0 

0 

0 

Aug. 

1,606,000 

513,000 

7,000 

0 

0 

0 

Sept. 

1,333,000 

171,000 

5,000 

0 

0 

0 

Oct. 

1,408,000 

0 

3,000 

0 

0 

0 

Nov. 

1,661,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 

4,276,000 

69,000 

2,253,000 

164,000 

0 

average 
1907 

2,309,000 

0 

0 

759.000 

0 

0 

Jan. 

2,486,000 

0 

0 

1,636,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

2,072,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

325,000 

250,000 

0 

April 

2,940,000 

684,000 

10,000 

0 

8  000 

0 

May 

2,884,000 

855.000 

12,000 

0 

0 

0 

June 

2,438,000 

941,000 

13,000 

0 

0 

0 

July 

1,818,000 

855,000 

10,000 

0 

0 

0 

Aug. 

1.244,000 

513,000 

6,000 

0 

0 

0 

Sept. 

977,000 

171,000 

4,000 

0 

0 

0 

Oct. 

1,063,000 

0 

3,000 

0 

0 

0 

Nov. 

1,316.000 

0 

0 

0 

0 

0 

Dec. 
Total  or 

4,276,000 

65,000 

4,792.000 

258,000 

0 

average 

256 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  3a  (Continued).     KENNETT 

COMPARISON  OF  WATER  YIELD 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 

Flood  control  by  reservoir  operating  diagram 

Maximum  controll'>d  flow  at  Red  Bluff  125,000  sec.-ft. 

Maximum  reservoir  space  required  454,000  ac.-ft. 

Estimated 

Year  and 
month 

run-off  at 

Irrigation 

dam  site  in 
acre-feet 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

draft  in 

acre-feet 

(no  deduction 

for  down- 
stream prior 

Evaporation 
in  acre-feet 

Release 

through  flood 

control  outlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

in  irrigation 

supply  in 

acre-feet 

rights) 

1908 

Jan. 

904,000 

1,795,000 

0 

0 

44.000 

0 

0 

Feb. 

970,000 

2,655,000 

0 

0 

1,073,000 

0 

0 

Mar. 

669,000 

2,552,000 

43.000 

0 

284,000 

0 

0 

April 

527,000 

2,894,000 

214.000 

7,000 

0 

260,000 

0 

May 

492,000 

2,940,000 

684.000 

10,000 

0 

0 

0 

June 

340,000 

2,738,000 

855,000 

11,000 

0 

0 

0 

July 

260,000 

2,212,000 

941,000 

12,000 

0 

0 

0 

Aug. 

229,000 

1,519,000 

855,000 

8.000 

0 

0 

0 

Sept. 

205,000 

885,000 

513,000 

5.000 

0 

0 

0 

Oct. 

235,000 

572,000 

171,000 

3,000 

0 

0 

0 

Nov. 

257,000 

633,000 

0 

2,000 

0 

0 

0 

Dec. 

267,000 

888,000 

0 

0 

0 

0 

0 

Total  or 
averagf 

5,355,000 

4,276,000 

58,000 

1,401.000 

260,000 

0 

1909 

Jan. 

3,260,000 

1,155,000 

0 

0 

1.909.000 

0 

0 

Feb. 

2,526,000 

2,506,000 

0 

0 

2,407,000 

0 

0 

Mar. 

977,000 

2,625,000 

43,000 

0 

650,000 

0 

0 

April 

756,000 

2,909,000 

214,000 

7,000 

35,000 

469,000 

0 

May 

581,000 

2,940,000 

(iS  1,000 

10.000 

0 

5,000 

0 

June 

410,000 

2,822,000 

855,000 

11.000 

0 

0 

0 

July 

308,000 

2,366,000 

941,000 

12.000 

0 

0 

0 

Aug. 

264,000 

1,721.000 

855,000 

9.000 

0 

0 

0 

Sept. 

246,000 

1,121,000 

513,000 

5.000 

0 

0 

0 

Oct. 

284,000 

849,000 

171,000 

3.000 

0 

0 

0 

Nov. 

538,000 

959,000 

0 

2.000 

0 

0 

0 

Dec. 
Total  or 
average 

721,000 

1,405,000 

0 

0 

0 

0 

0 

10,871.000 

4,276,000 

59,000 

5,001,000 

474,000 

0 

1910 

Jan. 

708,000 

2,216,000 

0 

0 

280,000 

0 

0 

Feb. 

847,000 

2,644.000 

0 

0 

717,000 

0 

0 

Mar. 

1,239,000 

2,774,000 

43,000 

0 

580,000 

441,000 

0 

April 

665,000 

2,940,000 

214.00(1 

7,000 

0 

444,000 

0 

May 

415,000 

2,940,000 

(>8t,00(l 

10,000 

0 

0 

0 

June 

282,000 

2,661,fK)0 

855.000 

11,000 

0 

0 

0 

July 

2?4,000 

2,077.000 

941,000 

11,000 

0 

0 

0 

Aug. 

236,000 

1,379,000 

855,000 

8,000 

0 

0 

0 

Sept. 

214,000 

752,000 

513,000 

4.000 

0 

0 

0 

Oct. 

231.000 

449,000 

171,000 

2.000 

0 

0 

0 

Nov. 

274,000 

.507,000 

0 

2.000 

0 

0 

0 

Dec. 
Total  or 
average 

436,000 

779,000 

0 

0 

0 

0 

0 

5,801,000 

4,276,000 

55,000 

1,586.000 

885,000 

0 

1911 

Jan. 

700,000 

1,215,000 

0 

0 

0 

0 

0 

Feb. 

848,000 

1.915,000 

0 

0 

172,000 

0 

0 

Mar. 

1,278,000 

2,-591,000 

43,000 

0 

1.013.000 

0 

0 

April 
May 

962,000 

2,813.000 

214,000 

7,000 

172.000 

442.000 

0 

671,000 

2.940,000 

684,000 

10,000 

0 

13,000 

0 

June 

431,000 

2,00'l,000 

855,000 

12,000 

0 

0 

0 

July 

287,000 

2,468,000 

941.000 

13,000 

0 

0 

0 

Aug. 

244,000 

1.8(11.(1011 

855,000 

10,000 

0 

0 

0 

Sept. 

231.000 

1,180,000 

513.000 

6,000 

0 

0 

0 

Oct. 

240,0(K) 

892.(M)0 

171,000 

3.000 

0 

0 

0 

Nov. 

241,000 

964.000 

0 

2,000 

0 

0 

0 

Dec. 

244,000 

1.203.000 

0 

0 

0 

0 

0 

Total  or 
average 

6.383,000 

4,276,000 

63,000 

1.357,000 

455,000 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


257 


RESERVOIR  ON  SACRAMENTO  RIVER. 
OPERATING  PRIMARILY  FOR  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  3,  page  112.) 

Seasona  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet; 


Flood  control,  holding  maximum  reservoir  space  required  (454,000  ac.-ff.) 

n  reserve  throughout  ^ood  season 

Maximum  controlled  flow  at  Red  Bluff  125, OOC 

sec.-ft. 

Irrigation 

Stage  of 

draft  in 

Release 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

Year  and 

reservoir  at 

beginning 

of  month  in 

acre-feet 

Tno  deduction 

for  down- 

Evaporation 
in  acre-feet 

through  flood 

control  outlets 

in  acre-feet 

in  irrigation 
supply  in 
acre-feet 

month 

acre-feet 

stream  prior 
rights) 

1908 

1,795,000 

0 

0 

213,000 

0 

0 

Jan. 

2,486,000 

0 

0 

970,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

626,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

58,000 

0 

e 

April 

2,734,000 

684,000 

10,000 

0 

0 

0 

May 

2,532,000 

855,000 

11,000 

0 

0 

0 

June 

2,006,000 

941,000 

11,000 

0 

0 

0 

July 

1,314,000 

855,000 

8,000 

0 

0 

0 

Aug. 

680,000 

513,000 

4,000 

0 

0 

0 

Sept. 

368,000 

171,000 

2,000 

0 

0 

0 

Oct. 

430,000 

0 

1,000 

0 

0 

0 

Nov. 

686,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 

4,276,000 

54,000 

1,867,000 

0 

0 

average 
1909 

953,000 

0 

0 

1,727,000 

0 

0 

Jan. 

2,486,000 

0 

0 

2,526,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

934,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

144,000 

0 

0 

April 

2,877,000 

684,000 

10,000 

0 

0 

0 

May 

2,764,000 

855,000 

11,000 

0 

0 

0 

June 

2,308,000 

941,000 

12,000 

0 

0 

0 

July 

1,663,000 

855,000 

9,000 

0 

0 

0 

Aug. 

1,063,000 

513,000 

5,000 

0 

0 

0 

Sept. 

791,000 

171,000 

3,000 

0 

0 

0 

Oct. 

901,000 

0 

2,000 

0 

0 

0 

Nov. 

1,437,000 

0 

0 

0 

0 

0 

Deo. 
Total  or 

4,276,000 

59,000 

5,331,000 

0 

0 

average 
1910 

2,158,000 

0 

0 

380,000 

0 

0 

Jan. 

2,485,000 

0 

0 

847,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

1,193,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

133,000 

0 

0 

April 

2,797,000 

684,000 

10,000 

0 

0 

0 

May 

2,518,000 

855,000 

11,000 

0 

0 

0 

June 

1,934,000 

941,000 

11,000 

0 

0 

0 

July 

1,236,000 

855,000 

7,000 

0 

0 

0 

Aug. 

610,000 

513,000 

4,000 

0 

0 

0 

Sept. 

307,000 

171,000 

2,000 

0 

0 

0 

Oct. 

365,000 

0 

1,000 

0 

0 

0 

Nov. 

638,000 

0 

0 

0 

0 

0 

Dec. 

Total  or 

4,276,000 

53,000 

2,.556,000 

0 

0 

average 
1911 

1,074,000 

0 

0 

0 

0 

0 

Jan. 

1,774.000 

0 

0 

136,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

1,235,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

263,000 

24,000 

0 

April 

2,940,000 

084,000 

10,000 

0 

13,000 

0 

May 

2,904,000 

855,000 

12,000 

0 

0 

0 

June 

2,468,000 

941,000 

13,000 

0 

0 

0 

July 

1,801,000 

855,000 

10,000 

0 

0 

0 

Aug. 

1,180,000 

513.000 

6,000 

0 

0 

0 

Sept. 

892,000 

171,000 

3,000 

0 

0 

0 

Oct. 

964,000 

0 

2,000 

0 

0 

0 

Nov. 

1,203,000 

0 

0 

U 

c 

0 

Dec. 
Total  or 

4,276,000 

■                  63,000 

1,634,000 

37,000 

0 

average 

258 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  3a  ^Continued).     KENNETT 

COMPARISON  OF  WATER  YIELD 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Flood  control  by  reservoir  operating  diagram 

Maximum 

controlled  flow  at  Red  Bluff  125 

000  sec.-ft. 

Maximum  reservoir  space  required  454,000  ac.-ft. 

Estimated 

Year  and 
month 

run-off  at 

Irrigation 

dam  site  in 
acre-feet 

Stage  of 
re8er\'oir  at 

beginning 
of  month  in 

acre-feet 

draft  in 

acre-feet 

(no  deduction 

for  down- 
stream prior 

Evaporation 
in  acre-feet 

Release 

through  flood 

control  outlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

in  irrigation 

supply  in 

acre-feet 

. 

rights) 

1912 

Jan. 

£17,000 

1,447,000 

0 

0 

0 

0 

0 

Feb. 

396,000 

1.964,000 

0 

0 

0 

0 

0 

Mar. 

635,000 

2.360.000 

43,000 

0 

0 

12.000 

0 

April 

487,000 

2.940.000 

214,000 

7,000 

0 

266,000 

0 

May 

714  000 

2,940.000 

684,000 

10,000 

0 

58,000 

0 

June 

405.000 

2,902,000 

855.000 

12.000 

0 

0 

0 

July 

274.000 

2,440.000 

941.000 

13,000 

0 

0 

0 

Aug. 

238,000 

1.760,000 

855.000 

9,000 

0 

0 

0 

Sept. 

242,000 

1.134,000 

513.000 

5.000 

0 

0 

0 

Oct. 

226,000 

8.58,000 

171,000 

3,000 

0 

0 

0 

Nov. 

432,000 

910,000 

0 

2.000 

0 

0 

0 

Dec. 

369,000 

1,340,000 

0 

0 

0 

0 

Total  or 
average 

4,935,000 

4,276,000 

61,000 

0 

336,000 

0 

1913 

Jan. 

763,000 

1,709,000 

0 

0 

0 

0 

0 

Feb. 

387,000 

2,472,000 

0 

0 

135,000 

0 

0 

Mar. 

441,000 

2,724,000 

43,000 

0 

37,oeo 

145,000 

0 

April 

685,000 

2,940,000 

214,000 

7.000 

0 

464,000 

0 

May 

521,000 

2,940,000 

684,000 

10,000 

0 

0 

0 

June 

321,000 

2.767,000 

855,000 

11,000 

0 

0 

0 

July 

263,000 

2.222,000 

941.000 

12,000 

0 

0 

0 

Aug. 

232,000 

1,532,000 

855.000 

8,000 

0 

0 

0 

Sept. 

190,000 

901,000 

513,000 

5  000 

0 

0 

0 

Oct. 

202,000 

573,000 

171.000 

3,000 

0 

0 

0 

Nov. 

316,000 

601,000 

0 

2,000 

0 

0 

0 

Dec. 
ToUl  or 
average 

696,000 

915,000 

0 

0 

0 

0 

0 

5,017,000 

4,276,000 

58,000 

172,000 

609,000 

0 

1914 

Jan. 

2,797,000 

1,611,000 

0 

0 

1,629,000 

0 

0 

Feb. 

1,359,000 

2,779,000 

0 

0 

1,364,000 

0 

0 

Mar. 

987,000 

2,774,000 

43,000 

0 

820,000 

0 

0 

April 
May 

1,137,000 

2.898,000 

214.000 

7,000 

30,000 

844,000 

0 

703,000 

2,940,000 

684,000 

10.000 

0 

37.000 

0 

June 

452,000 

2.912,000 

855,000 

12,000 

0 

0 

0 

July 

309,000 

2,497,000 

941,000 

13,000 

0 

0 

0 

Aug. 

248,000 

1,852,000 

855,000 

10,000 

0 

0 

0 

Sept. 

225,000 

1,235,000 

513,000 

6,000 

0 

0 

0 

Oct. 

269,000 

941,000 

171,000 

4,000 

0 

0 

0 

Nov. 

252,000 

1,035,000 

0 

3,000 

0 

0 

0 

Dec. 
Total  or 
average 

347,000 

1,284,000 

0 

0 

0 

0 

0 

9,085,000 

4,276,000 

65,000 

3,843,000 

881,000 

0 

1916 

Jan. 

895,000 

1,631,000 

0 

0 

38,000 

0 

0 

Feb, 

2,298,000 

2.488.000 

0 

0 

2,095,000 

0 

0 

Mar. 

1,264,000 

2,691,000 

43,000 

0 

985,000 

0 

0 

April 
May 

1,159,000 

2,927,000 

214,000 

7.000 

47,000 

878.000 

0 

1,256,000 

2,940.000 

684.000 

10.000 

0 

562,000 

0 

June 

572.000 

2,940,000 

855,000 

12.000 

0 

0 

0 

July 

343,000 

2,645,000 

941,000 

14.000 

0 

0 

0 

Aug. 

266,000 

2,033,000 

855,000 

10.000 

0 

0 

0 

Sept. 

215,000 

1,434,000 

513,000 

6.000 

0 

0 

0 

Oct. 

233,000 

1,130.000 

171,000 

4,000 

0 

0 

0 

Nov. 

254,000 

1,188,000 

0 

3,000 

0 

0 

0 

Dec. 
Total  or 

699,000 

1,439,000 

0 

0 

0 

0 

0 

averagn 

9,454.000 

4,276,000 

66,000 

3,165,000 

1,440,000 

0 

THE   CONTROL   OP   FLOODS   BY   RESERVOIRS. 


259 


RESERVOIR  ON  SACRAMENTO  RIVER. 
OPERATING  PRIMARILY  FOR  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  3,  page  112.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 


Flood  control,  holding  maximum  reservoir  space  required  (454,000  ac.-ft.) 

n  reserve  throughout  flood  season 

Maximum  controUed  flow  at  Red  Bluff  125,00C 

sec.-ft. 

Stage  of 
reservoir  at 
beginning 
of  month  in 

acre-feet 

Irrigation 

draft  in 

acre-feet 

(no  deduction 

for  down- 
stream prior 
rights) 

Evaporation 
in  acre-feet 

Release 

through  flood 

control  outlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

in  irrigation 

supply  in 

acre-feet 

Year  and 
month 

1912 

1,447,000 

0 

0 

0 

0 

0 

Jan. 

1,964,000 

0 

0 

0 

0 

0 

Feb. 

2,360,000 

43,000 

0 

466,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

45,000 

0 

0 

April 

2,707,000 

684,000 

10,000 

0 

0 

0 

May 

2,727,000 

855,000 

11,000 

0 

0 

0 

June 

2,266,000 

941,000 

12,000 

0 

0 

0 

July 

1,587,000 

855,000 

9,000 

0 

0 

0 

Aug. 

961,000 

513,000 

5,000 

0 

0 

0 

Sept. 

685,000 

171,000 

3,000 

0 

0 

0 

Oct. 

737,000 

0 

2,000 

0 

0 

0 

Nov. 

1,167,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,273,000 

59,000 

511,000 

0 

0 

1913 

1,536,000 

0 

0 

0 

0 

0 

Jan. 

2,299,000 

0 

0 

200,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

398,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

136,000 

0 

0 

April 

2,814,000 

684,000 

10,000 

0 

0 

0 

May 

2,641,000 

855,000 

11,000 

0 

0 

0 

June 

2,096,000 

941,000 

11,000 

0 

0 

0 

July 

1,407,000 

855,000 

8,000 

0 

0 

0 

Aug. 

776,000 

513,000 

4,000 

0 

0 

0 

Sept. 

449,000 

171,000 

2,000 

0 

0 

0 

Oct. 

478,000 

0 

2,000 

0 

0 

0 

Nov. 

792,000 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

4,276,000 

55,000 

734,000 

0 

0 

1914 

1,488,000 

0 

0 

1,799,000 

0 

■    0 

Jan. 

2,486,000 

0 

0 

1,359,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

944,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

235,000 

227,000 

0 

April 

2,940,000 

684,000 

10,000 

0 

37,000 

0 

May 

2,912,000 

855,000 

12,000 

0 

0 

0 

June 

2,497,000 

941,000 

13,000 

0 

0 

0 

July 

1,852,000 

855,000 

10,000 

0 

0 

0 

Aug. 

1,235,000 

513.000 

6,000 

0 

0 

0 

Sept. 

941.000 

171,000 

4,P00 

0 

0 

0 

Oct. 

1,035,000 

0 

3,000 

0 

0 

0 

Nov. 

1,284,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

65,000 

4,337,000 

264,000 

0 

1915 

1,631,000 

0 

0 

40,000 

0 

0 

Jan. 

2,486,000 

0 

0 

2,298,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

1,221,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

335,000 

149,000 

0 

April 

2.940,000 

684,000 

10,000 

0 

562,000 

0 

May 

2,940,000 

855,000 

12,000 

0 

0 

0 

June 

2,645,000 

941,000 

14,000 

0 

0 

0 

July 

2,033,000 

855.000 

10,000 

0 

0 

0 

Aug. 

1,434,000 

513,000 

6,000 

0 

0 

0 

Sept. 

1,130,000 

171,000 

4,000 

0 

0 

0 

Oct. 

1,188,000 

0 

3,000 

0 

0 

0 

Nov. 

1,439,000 

0 

0 

0 

1                           " 

0 

Dec. 
Total  or 
average 

4,276,000 

66,000 

3,894,000 

711,000 

0 

260 


WATER   RESOURCES  OF    CALIFORNIA. 


TABLE  3a  (Continued).     KENNETT 

COMPARISON  OF  WATER  YIELD 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 

Flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Estimated 

Maximum  reservoir  sjiace  required  454,000  ac.-ft. 

Year  and 
month 

run-off  at 

Irrigation 

dam  site  in 
acre-feet 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

draft  in 

acre-feet 

(no  deduction 

for  down- 
stream prior 

Evaporation 
in  acre-feet 

Release 

through  flood 

control  outlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

in  irrigation 

supply  in 

acre-feet 

rights) 

1916 

Jan. 

1.166,000 

2,138.000 

0 

0 

812,000 

0 

0 

Feb. 

1.616.000 

2,492,000 

0 

0 

1  566.000 

0 

0 

Mar. 

1,21.1.000 

2.,542,000 

43,000 

0 

836,000 

0 

0 

April 

678,000 

2.878.000 

214,000 

7.000 

9,000 

386,000 

0 

May 

485.000 

2,940,000 

684,000 

10.000 

0 

0 

0 

June 

353.000 

2.731,000 

855,000 

11,000 

0 

0 

0 

July 

316,000 

2.218,000 

941,000 

12,000 

0 

0 

0 

Aug. 

244.000 

1,. 581,000 

855,000 

9.000 

0 

0 

0 

Sept. 

21.3,000 

901,000 

513.000 

5,000 

0 

0 

0 

Oct. 

236,000 

656,000 

171,000 

3,000 

0 

0 

0 

Nov. 

242,000 

718.000 

0 

2.000 

0 

0 

0 

Dec. 
Total  or 
average 

363,000 

958,000 

0 

0 

0 

0 

0 

7,127,000 

4,276,000 

59.000 

3,223,000 

386.000 

0 

1917 

Jan. 

312.000 

1,321,000 

0 

0 

0 

0 

0 

Feb. 

760.000 

1,633,000 

0 

0 

0 

0 

0 

Mar. 

459,000 

2,393,000 

43,000 

0 

0 

0 

0 

April 

906,000 

2,809,000 

214,000 

7,000 

0 

5.54,000 

0 

May 

SSO.OOO 

2.940,000 

684,000 

10,000 

0 

5.000 

0 

June 

329,000 

2,821,000 

855,000 

11,000 

0 

0 

0 

July 

238,000 

2,284,000 

941,000 

12,000 

0 

0 

0 

Aug. 

214,000 

1,569,000 

855.000 

9.000 

0 

0 

0 

Sept. 

18.^000 

919,000 

513.000 

5,000 

0 

0 

0 

Oct. 

200,000 

586,000 

171,000 

3,000 

0 

0 

0 

Nov. 

224,000 

012,000 

0 

2,000 

0 

0 

0 

Pec. 
Total  or 
average 

298,000 

834,000 

0 

0 

0 

0 

0 

4,705,000 

4,276,000 

59,000 

0 

559,000 

0 

1918 

Jan. 

■  249,000 

1,132,000 

0 

0 

0 

0 

0 

Feb. 

399,000 

1,381,000 

0 

0 

0 

0 

0 

Mar. 

772,000 

1,780,000 

43,000 

0 

0 

0 

0 

April 

556,000 

2,,509,O00 

214,000 

7,000 

0 

0 

0 

May 

314,000 

2.844,000 

684,000 

10,000 

0 

0 

0 

June 

232,000 

2,464,000 

8,^5,000 

11.000 

0 

0 

0 

July 

200,000 

1,8.30,000 

941,000 

lO.OOO 

0 

0 

0 

Aug. 

192,000 

1,079,000 

855,000 

7,000 

0 

0 

0 

Sfipt. 

186.000 

409,000 

513.000 

3,000 

0 

0 

0 

Oct. 

258,000 

79,000 

171,000 

1,000 

0 

0 

0 

Nov. 

246.000 

165,000 

0 

1,000 

0 

0 

0 

Dec. 
Total  or 
average 

258,000 

410,000 

0 

0 

0 

0 

0 

3,862,000 

4.276,000 

50,000 

0 

0 

0 

1919 

Jan. 

587,000 

068,000 

0 

0 

0 

0 

0 

Feb. 

1.163,000 

1,2.55,000 

I) 

0 

0 

0 

0 

Mar. 

959,000 

2.418,000 

43,000 

0 

5011.000 

0 

0 

April 
May 

752,000 

2,825,000 

214,000 

7.000 

82,000 

334.000 

0 

438,000 

2,940.000 

084,000 

10.000 

0 

0 

0 

June 

2.52,000 

2.084,000 

855,000 

11,000 

0 

0 

0 

July 

219,000 

2,070,000 

941,000 

1!,000 

0 

0 

0 

Aug. 

199,000 

1,337,000 

855,000 

8,000 

0 

0 

0 

Sept. 

168,000 

673,000 

51.3.000 

4,000 

0 

0 

0 

Oct. 

203.000 

.324,000 

171,000 

2,000 

0 

0 

0 

Nov. 

186,000 

354,000 

0 

1.000 

0 

0 

0 

Dec. 
Total  or 
average 

180.000 

539,000 

0 

0 

0 

0 

0 

5,306.000 

4,276.000 

54,000 

591,000 

334,000 

0 

THE   CONTROL   OP   FLOODS   BY   RESERVOIRS. 


261 


RESERVOIR  ON  SACRAMENTO  RIVER. 
OPERATING  PRIMARILY  FOR  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  3,  page  1 12.) 

Seasona   irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 


Flood  control,  holding  maximum  reservoir  space  required  (454,000  ac.-ft.) 

in  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Stage  of 

Irrigation 
draft  in 

Release 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

Year  and 
month 

reservoir  at 
beginning 

of  month  in 
acre-feet 

acre-feet 
fno  deduction 

for  down- 
stream prior 

Evaporation 
in  acre-feet 

through  flood 

controloutlets 

in  acre-feet 

in  irrigation 
supply  in 
acre-feet 

rights) 

1918 

2,138,000 

0 

0 

818.000 

0 

0 

Jan. 

2,486,000 

0 

0 

1,616,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

1,172,000 

0 

0 

Mar. 

2,486,000 

214.000 

7,000 

129,000 

0 

0 

April 

2,814,000 

684,000 

10,000 

0 

0 

0 

May 

2,605,000 

855,000 

11,000 

0 

0 

0 

June 

2,092,000 

941,000 

11,000 

0 

0 

0 

July 

1,456,000 

855.000 

8,000 

0 

0 

0 

Aug. 

837,000 

513,000 

4.000 

0 

0 

0 

Sept. 

533,000 

171,000 

2.000 

0 

0 

0 

Oct. 

596,000 

0 

2,000 

0 

0 

0 

Nov. 

836,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

55,000 

3.735,000 

0 

0 

1917 

1,199,000 

0 

0 

0 

0 

0 

Jan. 

1,511,000 

0 

0 

0 

0 

0 

Feb. 

2,271,000 

43,000 

0 

201,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

122,000 

109,000 

0 

April 

2,940,000 

681,000 

10,000 

0 

5,000 

0 

May 

2  821,000 

855,000 

11,000 

0 

0 

0 

June 

2.284,000 

941,000 

12,000 

0 

0 

0 

July 

1,569,000 

855,000 

9,000 

0 

0 

0 

Aug. 

919,000 

513,000 

5,000 

0 

0 

0 

Sept. 

586,000 

171,000 

3,000 

0 

0 

0 

Oct. 

612.000 

0 

2,000 

0 

0 

0 

Nov. 

834.000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

59,000 

323,000 

114,000 

0 

1918 

1,132,000 

0 

0 

0 

0 

0 

Jan. 

1,381,000 

0 

0 

0 

0 

0 

Feb. 

1,780,000 

43,000 

0 

23,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

87,000 

0 

0 

April 

2,734,000 

684,000 

10,000 

0 

0 

0 

May 

2.354,000 

855,000 

10,000 

0 

0 

0 

June 

1,721.000 

941,000 

10,000 

0 

0 

0 

July 

970.000 

855,000 

6,000 

0 

0 

0 

Aug. 

301.000 

485,000 

2,000 

0 

0 

28,000 

Sept. 

0 

171,000 

0 

0 

0 

0 

Oct. 

87,000 

0 

0 

0 

0 

0 

Nov. 

333.000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,248,000 

45,000 

110,000 

0 

28,000 

1919 

591,000 

0 

0 

0 

0 

0 

Jan. 

1,178,000 

0 

0 

0 

0 

0 

Feb. 

2,341.000 

43,000 

0 

771,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

177.000 

0 

0 

April 

2.840,000 

684,000 

10,000 

0 

0 

0 

May 

2,.58'1,000 

855,000 

11,000 

0 

0 

0 

June 

1,970,000 

941,000 

11,000 

0 

0 

0 

July 

1,237,000 

855,000 

7,000 

0 

0 

0 

Aug. 

574,000 

513,000 

3,000 

0 

0 

0 

Sept. 

226,000 

171,000 

1,000 

0 

0 

0 

Oct. 

257,000 

0 

1,000 

0 

0 

0 

Nov. 

442.000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

51,000 

948,000 

0 

0 

262 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  3a  (Continued).     KENNETT 

COMPARISON  OF  WATER  YIELD 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 

Flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125 

000  sec.-ft. 

Maximum  reservoir  space  required  454,000  ac.-ft. 

Estimated 
run-off  at 

Year  and 
month 

Irrigation 

dam  site  in 
acre-feet 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

draft  in 

acre-feet 

(no  deduction 

for  down- 
stream prior 

Evaporation 
in  acre-feet 

Release 

through  flood 

control  outlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

in  irrigation 

supply  in 

acre-feet 

rights) 

1920 

Jan. 

207.000 

719,000 

0 

0 

0 

0 

0 

Feb. 

176.000 

926,000 

0 

0 

0 

0 

0 

Mar. 

372,000 

1,102,000 

43,000 

0 

0 

0 

0 

April 

493,000 

1,431,000 

214,000 

5,000 

0 

0 

0 

May 

286,000 

1,705,000 

684,000 

7,000 

0 

0 

0 

June 

216,000 

1,300,000 

855,000 

7,000 

0 

0 

0 

July 

192.000 

654,000 

841,000 

5,000 

0 

0 

100.000 

Aug. 

176.000 

0 

176,000 

0 

0 

0 

679.000 

Sept. 

140.000 

0 

140,000 

0 

0 

0 

373,000 

Oct. 

180,000 

0 

168,000 

0 

0 

0 

3,000 

Nov. 

896,000 

12,000 

0 

0 

0 

0 

0 

Dec. 

1,121,000 

908,000 

0 

0 

0 

0 

0 

Total  or 

average 

4,455,000 

3,121,000 

24,000 

0 

0 

1,155,000 

1921 

Jan. 

1.492,000 

2,029,000 

0 

0 

868,000 

0 

0 

Feb. 

1,035,000 

2,653,000 

0 

0 

1.126,000 

0 

0 

Mar. 

982,000 

2,562,000 

43,000 

0 

679,000 

0 

0 

April 

559,000 

2,822.000 

214,000 

7,000 

9,000 

211,000 

0 

May 

493.000 

2,940,000 

684.000 

10,000 

0 

0 

0 

June 

316.000 

2,739.000 

855,000 

11,000 

0 

0 

0 

Jjly 

220,000 

2,189,000 

941,000 

12,000 

0 

0 

0 

Aug. 

192,000 

1,456,000 

8.55,000 

8,000 

0 

0 

0 

Sept. 

175,000 

785,000 

513,003 

4,000 

0 

0 

0 

Oct. 

196,000 

443,000 

171,000 

2,000 

0 

0 

0 

Nov. 

205,000 

466,000 

0 

2,000 

0 

0 

0 

Doc. 

390,000 

669,000 

0 

0 

0 

0 

0 

Total  or 
average 

6.255,000 

4,276,000 

56,000 

2,682,000 

211,000 

0 

1922 

Jan. 

300,000 

1,059,000 

0 

0 

0 

0 

0 

Feb. 

679,000 

1,359,000 

0 

0 

0 

0 

0 

Mar. 

567,000 

2,038,000 

43,000 

0 

0 

0 

0 

April 

604,000 

2,562.000 

214,000 

7,000 

0 

5,000 

0 

May 

577,000 

2.940,000 

684,000 

10,000 

0 

0 

0 

June 

317,000 

2,823,000 

855,000 

11,000 

0 

0 

0 

July 

203,000 

2,274,000 

941,000 

12.000 

0 

0 

0 

Aug. 

182,000 

1,. 524,000 

855,000 

8.000 

0 

0 

0 

Sept. 

161,000 

843,000 

513,000 

4,000 

0 

0 

0 

Oct. 

208,000 

487,000 

171,000 

2,000 

0 

0 

0 

Nov. 

244,000 

522,000 

0 

2,000 

0 

0 

0 

Dec. 

462,000 

764,000 

0 

0 

0 

0 

0 

Total  or 
average 

4,5(M,000 

4.276,000 

56,000 

0 

5,000 

0 

1923 

Jan. 

467,000 

1,226,000 

0 

0 

0 

0 

0 

Feb. 

297,000 

1,693,000 

0 

0 

0 

0 

0 

Mar. 

287,000 

1,990.000 

43.000 

0 

0 

0 

0 

April 

632,000 

2,2.34,000 

214,000 

6,000 

0 

0 

0 

May 

322,000 

2,646,000 

684,000 

10,000 

0 

0 

0 

June 

236,000 

2.274,000 

855.000 

10,000 

0 

0 

0 

July 

184,000 

1,64^,000 

941,000 

10,000 

0 

0 

0 

Aug. 

165,000 

878,000 

855,000 

6,000 

0 

0 

0 

Sept. 

157.000 

182,000 

338,000 

1,000 

0 

0 

175,000 

Oct. 

187,000 

0 

171.000 

0 

0 

0 

0 

Nov. 

176,000 

16.000 

0 

0 

0 

0 

0 

Dec. 

184.000 

192.000 

0 

0 

0 

0 

0 

Total  or 
average 

3,294.000 

4,101,000 

43,000 

0 

0 

175,000 

TUE   CONTROL   OP   FLOODS   BY   RESERVOIRS. 


263 


RESERVOIR  ON  SACRAMENTO  RIVER. 
OPERATING  PRIMARILY  FOR  IRRIGATION 

FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

many,  see  Table  3,  page  112.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 


Flood  control,  holding  maximum  reservoir  space  required  (454,000  ac.-ft.) 

in  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Irrigation 

draft  in 

acre-feet 

(no  deduction 

for  down- 
stream prior 
rights) 

Evaporation 
in  acre-feet 

Release 

through  flood 

control  outlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

in  irrigation 

supply  in 

acre-feet 

Year  and 
month 

1920 

622,000 

0 

0 

0 

0 

0 

Jan.    • 

829,000 

0 

0 

0 

0 

0 

Feb. 

1,005,000 

43,000 

0 

0 

0 

0 

Mar. 

1,334,000 

214,000 

4,000 

0 

0 

0 

April 

1,609,000 

684,000 

7,000 

0 

0 

0 

May 

1,204,000 

855,000 

6.000 

0 

0 

0 

June 

559,000 

746,000 

5,000 

0 

0 

195,000 

July 

0 

176,000 

0 

0 

0 

679,000 

Aug. 

0 

140,000 

0 

0 

0 

373,000 

Sept. 

0 

168,000 

0 

0 

0 

3,000 

Oct. 

12,000 

0 

0 

0 

0 

0 

Nov. 

908,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 

3,026,000 

22,000 

0 

0 

1,250,000 

average 
1921 

2,029,000 

0 

0 

1,035,000 

0 

0 

Jan. 

2,486,000 

0 

0 

1,035,000 

0 

0 

Feb. 

2,486,000 

43,000 

0 

939,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

110,000 

0 

0 

April 

2,714,000 

684,000 

10,000 

0 

0 

0 

May 

2,513,000 

855,000 

11,000 

0 

0 

0 

June 

1,963,000 

941,000 

11.000 

0 

0 

0 

July 

1,231,000 

855,000 

7.000 

0 

0 

0 

Aug. 

561.000 

513,000 

3,000 

0 

0 

0 

Sept. 

220,000 

171,000 

1,000 

0 

0 

0 

Oct. 

244,000 

0 

1,000 

0 

Nov. 

448,000 

0 

0 

0 

0 

0 

Dec. 

Total  or 

4,276,000 

51,000 

3,119,000 

0 

0 

average 
1922 

838,000 

0 

0 

0 

0 

0 

Jan. 

1,138,000 

0 

0 

0 

0 

0 

Feb. 

1,817,000 

43,000 

0 

0 

0 

0 

Mar. 

2.341,000 

214,000 

6,000 

2,000 

0 

0 

April 

2,723,000 

681,000 

10,000 

0 

0 

0 

May 

2,606.000 

855,000 

11.000 

0 

0 

0 

June 

2,057,000 

941,000 

11,000 

0 

0 

0 

July 

1,308,000 

855,000 

8,000 

0 

0 

0 

Aug. 

627,000 

513,000 

4,000 

0 

0 

0 

Sept. 

271,000 

171,000 

2,000 

0 

0 

0 

Oct. 

306,000 

0 

1,000 

0 

0 

0 

Nov. 

549,000 

0 

0 

0 

0 

0 

Dec. 

Total  or 

4,276,000 

53,000 

2,000 

0 

0 

average 
1923 

1,011,000 

0 

0 

0 

0 

0 

Jan. 

1,478,000 

0 

0 

0 

0 

0 

Feb. 

1.775,000 

43,000 

0 

0 

0 

0 

Mar. 

2,019,000 

214,000 

0,000 

0 

0 

0 

.4pril 

2,431,000 

684,000 

9,000 

0 

0 

0 

May 

2,060,000 

855,000 

9,000 

0 

0 

0 

June 

1,432,000 

941,000 

9,000 

0 

0 

0 

July 

666,000 

820,000 

5,000 

0 

0 

29,000 

Aug. 

0 

157,000 

0 

0 

0 

356,000 

Sept. 

0 

171,000 

0 

0 

0 

0 

Oct. 

16,000 

0 

0 

0 

0 

0 

Nov. 

192,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

j             3,891,000 

38,000 

0 

0 

385,000 

264 


WATER   RESOURCES   OF    CALIFORNIA. 


TABLE  3a  (Concluded).     KENNETT 

COMPARISON  OF  WATER  YIELD 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 

Flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow 

It  Red  Bluflt  125 

000  sec.-f  t. 

Maximum  reservoir  space  required  454,000  ac.-ft. 

Estimated 

run-off  at 

dam  site  in 

acre-feet 

Year  and 
month 

Stage  of 
reservoir  at 
beginning 
of  month  in 

Irrigation 
draft  in 
acre-feet 
(no  deduction 
for  down- 

Evaporation 
in  acre-feet 

Release 

through  flood 

controloutlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

in  irrigation 

supply  in 

acre-feet 

stream  prior 

acre-feet 

rights) 

1924 

Jan. 

203,000 

376,000 

0 

0 

0 

0 

0 

Feb. 

332,000 

579,000 

0 

0 

0 

0 

0 

Mar. 

200,000 

911,000 

43,000 

0 

0 

0 

0 

April 

176.000 

1,068,000 

214,000 

4,000 

0 

0 

0 

May 

155,000 

1,026,000 

684,000 

5,000 

0 

0 

0 

June 

141,000 

492,000 

629,000 

4,000 

0 

0 

226,000 

July 

140.000 

0 

140,000 

0 

0 

0 

801.000 

Aug. 

140,000 

0 

140.000 

0 

0 

0 

715,000 

Sept. 

128,000 

0 

128,000 

0 

0 

0 

385,000 

Oct. 

178,000 

0 

158,000 

0 

0 

0 

13,000 

Nov. 

317,000 

20,000 

0 

0 

0 

0 

0 

Dec. 

321,000 

337,000 

0 

0 

0 

0 

0 

Total  or 

average 

2,431,000 

2,136,000 

13,000 

0 

0 

2,140,000 

1925 

Jan. 

301,000 

658,000 

0 

0 

0 

0 

0 

Feb. 

1,769,000 

959,000 

0 

0 

200.000 

0 

0 

Mar. 

563,000 

2,528,000 

43,000 

0 

232,000 

0 

0 

April 

926,000 

2,816.000 

214,000 

7,000 

94,000 

487,000 

0 

May 

474.000 

2,940,000 

684,000 

10,000 

0 

0 

0 

June 

276.000 

2.720,000 

855,000 

11.000 

0 

0 

0 

July 

173,000 

2,1.30,000 

941,000 

11,000 

0 

0 

0 

Aug. 

167,000 

1,.351.000 

855,000 

8,000 

0 

0 

0 

Sept. 

163,000 

655,000 

513,000 

4,000 

0 

0 

0 

Oct. 

181,000 

.301,000 

171,000 

2,000 

0 

0 

0 

Nov. 

192,000 

309,000 

0 

1,000 

0 

0 

0 

Dec. 

235,000 

£00,000 

0 

0 

0 

0 

0 

Total  or 
average 

5,420,000 

4,276,000 

54,000 

526,000 

487,000 

0 

Total  for 

30-year 

period. 

1896-1926 

188,012,000 

124.570,000 

1.641,000 

49,509.000 

13,417,000 

3,710,000 

Average 
for 

30-year 

period, 

1896-1926 

6,267.000 

4,152,000 

55.000 

1,650,000 

447,000 

124,000 

THE    CONTROL   OK    FLOODS    BY    KERERVOIRS. 


265 


RESERVOIR  ON  SACRAMENTO  RIVER. 
OPERATING  PRIMARILY  FOR  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  3,  page  1 12.) 

Seasonal  irrigation  yield  (deficiency  in  supply  one  year  in  ten,  no 

deduction  for  downstream  prior  rights)  4,276,000  acre-feet. 


Flood  control,  holding  maximum  reservoir  space  required  f454,000  ac.-ft.) 

In  reserve  throughout  f'ood  season 

Maximum  controlled  flow  at  Red  Bluff  125,000  see.-ft. 

Irrigation 

Year  and 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

draft  in 

acre-feet 

(no  deduction 

for  down- 
stream prior 
rights) 

Evaporation 
in  acre-feet 

Release 

through  flood 

control  outlets 

in  acre-feet 

Waste  over 

spillway  in 

acre-feet 

Deficiency 

in  irrigation 

supply  in 

acre-feet 

month 

1924 

376,000 

0 

0 

0 

0 

0 

Jan. 

579,000 

0 

0 

0 

0 

0 

Feb. 

911,000 

43,000 

0 

0 

0 

0 

Mar. 

1,068.000 

214,000 

4,000 

0 

0 

0 

April 

1,026,000 

684,000 

5,000 

0 

0 

0 

May 

492,000 

629,000 

4,000 

0 

0 

226,000 

June 

0 

140,000 

0 

0 

0 

801,000 

July 

0 

140,000 

0 

0 

0 

715,000 

Aug. 

0 

128,000 

0 

0 

0 

385,000 

Sept. 

0 

158,000 

0 

0 

0 

13,000 

Oct. 

20,000 

0 

0 

0 

0 

0 

Nov. 

337,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

2,136,000 

13,000 

0 

0 

2,140,000 

1925 

658,000 

0 

0 

0 

0 

0 

Jan. 

959,000 

0 

0 

242,000 

0 

0 

Feb. 

2,486.000 

43,000 

0 

520,000 

0 

0 

Mar. 

2,486,000 

214,000 

7,000 

197,000 

54.000 

0 

April 

2,940,000 

684,000 

10,000 

0 

0 

0 

May 

2,720,000 

855,000 

11,000 

0 

0 

0 

June 

2,130,000 

941,000 

11,000 

0 

0 

0 

July 

1,351,000 

855,000 

8,000 

0 

0 

0 

Aug. 

655,000 

513,000 

4,000 

0 

0 

0 

Sept. 

301,000 

171,000 

2,000 

0 

0 

0 

Oct. 

309,000 

0 

1,000 

0 

0 

0 

Nov. 

500,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4,276,000 

54,000 

959,000 

54,000 

0 

Total  for 

30-year 

period. 

124,224,000 

1,582,000 

60,257,000 

3,074,000 

4,056,000 

1896-1926 

Average 
for 

30-year 
period, 

4,141,000 

53,000 

2,009,000 

102,000 

135,000 

1896-1926 

17—52411 


li6G 


WATEK   RESOURCES   OP    ('ALIKORNIA. 


TABLE  4a.     KENNETT  RESER 

COMPARISON  OF  WATER  AND  POWER  YIELD,  OPERATING  PRI 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 
Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Flood  control  by  reservoir  operating  diagram 

Maximum  controllecl  flow  at  Red  Bluff  1 25,000  sec.-ft. 

Esti- 

Maximum reservoir  space 

equired  454,000  ac- 

ft. 

mated 
run-off 

Year  and 

at 

Stage  of 

Power  draft 

Release 

Average  power  yield 

month 

dam 

reservoir 

through  turbines  in 

through 

Waste 

Average 

power 

head  in 

feet 

it 

kilowatts 

site 

at 

acre-feet 

Evapora- 

flood 

over 

(Load  {actor=0.75) 

in 
acre-feet 

beginning 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

of 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 

acre-feet 

acre-feet 

•Primary 

Second- 
ary 

Total 

1896 

Jan. 

1,980,000 

2.256,000 

242,000 

118,000 

0 

1,367,000 

0 

383 

97,400 

47.200     144,600 

Feb. 

474,000 

2,509,000 

231,000        51.000 

0 

50,000 

0 

396 

98,400 

22,300;    120.700 

Mar. 

738,000 

2,651.000 

247,000        49.000 

0 

0 

153,000 

405 

104.200 

20,4001    124,600 

April 

891,000 

2,940,000 

249,000 

231,000 

7,000 

0 

404,000 

408 

109,000 

101,000    210,000 

May 

1,194,000 

2,940,000 

279,000 

219,000 

10,000 

0 

686,000 

407 

117,500 

92,500|    210,000 

June 

536,000 

2,940,000 

283,000 

196,000 

12.000 

0 

80,000 

410 

124,200 

85,800 1    210.000 

July 

313,000 

2,905,000 

298,000       151,000 

14,000 

0 

0 

407 

125,400 

63,700!    189,100 

Aug. 

268,000 

2,755,000 

304.000       102,000 

13,000 

0 

0 

400 

126,700 

42,500     169,200 

Sept. 

258,000 

2,604,000 

282,000[      101,000 

10,000 

0 

0 

394 

120,000 

42.800,    162.800 

Oct. 

262,000 

2,469.000 

278,000 

75,000 

7,000 

0 

0 

388 

113,400 

30,500     143,900 

Nov. 

472,000 

2,371,000 

264,000 

161,000 

5,000 

0 

0 

385 

110,300 

66.800'    177,100 

Dec. 

920,000 

2,413,000 

268,000 

247,000 

0 

223,000 

0 

390 

109,400 

100,600 

210,000 

Total  or 
average 

8,306,000 

3,225.000 

1,701,000 

78,000 

1.040.000 

1,323,000 

398 

113,000 

59.700 

172.700 

1897 

Jan. 

577,000 

2,595,000 

238,000 

174,000 

0 

252,000 

0 

392 

97.400 

71,000 

168.400 

Feb. 

1,338,000 

2,508,000 

228.000 

242,000 

0 

846,000 

0 

385 

101,900 

108,100 

210.000 

Mar. 

737,000 

2,530,000 

251,000 

130,000 

0 

75,000 

0 

398 

10*.200 

53,200!    157,400 

April 

858,000 

2,811,000 

249,000 

186,000 

7,000 

2,000 

285,000 

408 

109,000 

81,400     190,400 

May 

554,000 

2,940.000 

276,000 

195,000 

10,000 

0 

73,000 

411 

117,500 

82,500     200,000 

June 

310,000 

2,940,000 

283,000 

73,000 

12,000 

0 

0 

410 

124,200 

32,100i    1.56,300 

July 

275,000 

2,882,000 

298,000 

90,000 

14,000 

0 

0 

407 

125,400 

37.900 1    163,300 

Aug. 

251,000 

2,755,000 

305,000 

87,000 

13,000 

0 

0 

400 

120.700 

36,2001    162.900 

Sept. 

247,000 

2,604,000 

282,000 

90,000 

10,000 

0 

0 

394 

120.000 

38,2001    158,200 

Oct. 

202,000 

2,469,000 

278,000 

75,000 

7,000 

0 

0 

388 

113,400 

30,500     143,900 

Nov. 

274,000 

2,371,000 

265,000 

97,000 

5,000 

0 

0 

382 

110,300 

40.300     150.600 

Dec. 
Total  or 
average 

366.000 

2,278,000 

274,000 

113,000 

0 

0 

0 

380 

109,400 

45,200     154.600 

6.052,000 

3,227.000 

1,552,000 

78,000 

1,175,000 

358,000 

396 

113.400 

54.300 

167.700 

1898 

Jan. 

257,000 

2,257,000 

243.000 

0 

0 

0 

0 

380 

97.400 

0 

97.400 

Feb. 

478,000 

2,271,000 

220.000 

0 

0 

0 

0 

388 

101.900 

0 

101,900 

Mar. 

380,000 

2.523,000 

248,000 

0 

0 

0 

0 

397 

104.200 

0 

104.200 

April 
May 

274,000 

2,655,000 

253,000 

0 

7,000 

0 

0 

400 

109.000 

0     109.000 

300,000 

2,669.000 

281,000 

0 

10,000 

0 

0 

401 

117,500 

0     117,500 

June 

30t,00f 

2,678,000 

287.000 

0 

11,000 

( 

0 

401 

124,200 

O'    124.200 

July 

237,000 

2,084,000 

301.000 

c 

14,000 

0 

0 

400 

125,400 

O;    125,400 

Aug. 

225,000 

2,606,000 

307.000 

c 

12,000 

0 

0 

396 

126,700 

0     126.700 

S.pt. 

198.000 

2,512,000 

284,000 

c 

9,000 

0 

0 

390 

120,000 

Oi    120.000 

Oct. 

221,00C 

2,417,000 

279,000 

0 

7,000 

0 

0 

386 

113,400 

0.    113,400 

Nov. 

217,00C 

2,352,000 

265.000 

21,00C 

5.000 

0 

0 

383 

110,300 

8,800     119.100 

Dec. 

217,00C 

2,278,000 

274,000 

0 

0 

0 

0 

380 

109.400 

0     109.400 

Total  or 
average 

1 

3,308,00C 

3.248.000 

21.00C 

76,000 

0 

0 

392 

113.400 

700    114.100 

•Total  prinuiry  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OF   FI-OODS   BY   RESERVOIRS. 


267 


VOIR  ON  SACRAMENTO  RIVER. 

MARILY  FOR  POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  4,  page  1 14.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.F.  =  0.80. 


Flood  control, 

folding  maximum  space  required  (454,000  ac 

-ft.)  in  reserve 

throughout  flood  season 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-lt. 

Stage  of 

Power  draft 

Release 

Average  power 

yield 

Year  and 

reservoir 

through  turbines  in 

through 

Waste 

Average 

in  kilowatts 

month 

at 

acre 

-feet 

Evapora- 

flood 

over 

(Load  factor= 

).75) 

beginning 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

of 

mgnth  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-feet 

*Primary 

Second- 
ary 

Total 

1896 

2,075,000 

238,000 

132,000 

0 

1,199.000 

0 

374 

94,100 

52,300 

146,400 

Jan. 

2,486,000 

226,000 

182,000 

0 

06,000 

0 

390 

95,100 

79,300 

174,400 

Feb. 

2,486,000 

246,000 

225,000 

0 

267,000 

0 

389 

100,500 

91,400 

191,900 

Mar. 

2,486,000 

245,000 

115,000 

7,000 

70,000 

0 

398 

105,300 

49,000 

154,300 

April 

2,940,000 

268,000 

228,000 

10,000 

0 

688,000 

408 

113,300 

96,700 

210,000 

May 

2,940,000 

274,000 

205,000 

12,000 

0 

80,000 

411 

119,700 

90,300 

210,000 

June 

2,905,000 

287,000 

212,000 

14,000 

0 

0 

407 

121,100 

88,900 

210,000 

July 

2,705,000 

296,000 

198,000 

13,000 

0 

0 

395 

122,300 

81,600 

203,900 

Aug. 

2,466,000 

277,000 

100,000 

9,000 

0 

0 

386 

115,800 

41,800 

157,600 

Sept. 

2,338,000 

272,000 

75,000 

7,000 

0 

0 

382 

109,500 

30,100 

139,600 

Oct. 

2,246,000 

258,000 

170,000 

4,000 

0 

0 

378 

106,500 

69,700 

176,200 

Nov. 

2,286,000 

202,000 

260,000 

0 

198,000 

0 

383 

105,600 

104,400 

210,000 

Dec. 
Total  or 
average 

3,149,000 

2,102,000 

70,000 

1,800,000 

768,000 

392 

109,100 

73,000 

182,100 

2,486,000 

230,000 

205,000 

0 

142,000 

0 

390 

94,100 

83,300 

177,400 

1897 

Jan. 

2,486,000 

229,000 

250,000 

0 

868,000 

0 

384 

98,500 

111,500 

210,000 

Feb. 

2,486,000 

247,000 

264,000 

0 

226,000 

Q 

388 

100,500 

107,000 

207,500 

Mar. 

2,486,000 

245,000 

156,000 

7,000 

70,000 

0 

398 

105,300 

60,500 

171,800 

April 

2,866,000 

267,000 

228,000 

10,000 

0 

0 

410 

113,300 

96,700 

210,000 

May 

2,915,000 

275,000 

208,000 

12,000 

0 

0 

406 

119,700 

90,300 

210,000 

June 

2,730,000 

291,000 

90,000 

14,000 

0 

0 

400 

121,100 

37,600 

158,700 

July 

2,610,000 

298,000 

88,000 

12,000 

0 

0 

394 

122,300 

36,200 

158,500 

Aug. 

2,466,000 

277,000 

89,000 

9,000 

0 

0 

386 

115,800 

37,200 

153,000 

Sept. 

2,338,000 

272,000 

75,000 

7,000 

0 

0 

382 

109,500 

30,100 

139,600 

Oct. 

2,246,000 

259,000 

98,000 

4,000 

0 

0 

377 

100,500 

40,300 

146,800 

Nov. 

2,159.000 

268,000 

182,000 

0 

0 

0 

372 

105,000 

71,500 

177,100 

Dec. 
Total  or 
average 

3,149.000 

1,933,000 

75,000 

1,306,000 

0 

391 

109,400 

67,100 

170,500 

2,075,000 

240,000 

0 

0 

0 

0 

370 

94,100 

0 

94,100 

1898 

Jan. 

2,092,000 

221,000 

0 

0 

0 

0 

378 

98,500 

0 

98,500 

Feb 

2,346,000 

245,000 

0 

0 

0 

0 

391 

100,500 

0 

109,500 

Mar. 

2,481.000 

247,000 

0 

7,000 

0 

0 

394 

105,300 

0 

105,300 

April 

2,501.000 

276,000 

0 

9,000 

0 

0 

394 

113,300 

0 

113,300 

May 

2,516,000 

282,000 

0 

11,000 

0 

0 

394 

119,700 

0 

119,700 

June 

2,527,000 

296,900 

0 

13,000 

0 

0 

392 

121,100 

0 

121,100 

July 

2,45.),000 

301,000 

0 

12,000 

0 

0 

388 

122,300 

0 

122,300 

Aug. 

2,367,000 

278,000 

0 

9,000 

0 

0 

384 

115,800 

0 

115,800 

Sept. 

2.278.000 

274,000 

0 

7,000 

0 

0 

380 

109,500 

0 

109,500 

Oct. 

2,218,000 

259,000 

13,000 

4,000 

0 

0 

376 

106,500 

5,300 

111,800 

Nov. 

2,159,000 

268,000 

33,000 

0 

0 

0 

372 

105,600 

13,000 

118,600 

Dec. 
Total  or 
average 

3,190,000 

46,000 

72,000 

0 

0 

384 

109,400 

1,500 

110,900 

268 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  4a  (Continued).     KENNETT 

COMPARISON  OF  WATER  AND  POWER  YIELD,  OPERATING  PRI 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Compute 

(For  corresponding  yearly  sum 
Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Flood  control  by  reservoir  operatin 

a  diagram 

Maximum  controlled  flow  at  Red  Bluff  125,000  scc.-ft. 

Esti- 

Maximum reservoir  space 

required  454,000  ac. 

-ft. 

mated 
run-off 

Year  and 

at 

Stage  of 

Power  draft 

Release 

Average  power  yield 

month 

dam 

reservoir 

through  turbines  in 

through 

Waste 

Average 

in  kilowatts 

site 

a 

acre 

-feet 

Evapora- 

flood 

over 

(Load  factor=0.75) 

in 
acre-feet 

beginning 
of 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-feet 

*Primary 

Second- 
ary 

Total 

1899 

Jan. 

605,000 

2,221,000 

241,000 

45,000 

0 

2,000 

0 

387 

97,400 

18,400!    115,800 

Feb. 

253,000 

2,538,000 

223,000 

0 

0 

0 

0 

390 

101,900 

0'    101,900 

Mar. 

900,000 

2.508,000 

249,000 

57,000 

0 

278,000 

0 

399 

104,200 

23,900!    128,100 

April 

456,000 

2,884,000 

246,000 

140,000 

7,000 

0 

7.000 

412 

109,000 

61,500,    170,500 

May 

330,000 

2,940,000 

276,000 

44,000 

10,000 

0 

0 

412 

117.500 

18,800 

136,300 

June 

302,000 

2,940,000 

282,000 

59,000 

12,000 

0 

7,000 

411 

124,200 

2,5,700 

149,900 

July 

240,000 

2,882,000 

298,000 

55,000 

14,000 

0 

0 

407 

125,400 

23,100 

148,500 

Aug. 

224,000 

2,755,000!     304,000 

58,000 

13,000 

0 

0 

400 

126,700 

24,200 

150,900 

Sept. 

197,000 

2,604,000|     282,000 

40,000 

10,000 

0 

0 

394 

120,000 

16,900 

136,900 

Oct. 

252,000 

2,469,000|     278,000 

05,000 

7,000 

0 

0 

388 

113.400 

26,500 

139,900 

Nov. 

645,000 

2,371.000!     264,000 

187,000 

5,000 

0 

0 

386 

110,300 

77,900 

188,200 

Dec. 
Total  or 
average 

646,000 

2,560,000 

266,000 

244,000 

0 

108,000 

0 

390 

109,400 

100,600|    210,000 

5,050,000 

3,209,000 

994,000 

78,000 

388,000 

14,000 

399 

113,400 

35,000 

148,400 

1900 

Jan. 

i,2'jy,ooo 

2,588,000 

240,000 

274,000 

0 

883,000 

0 

388 

97,400 

110,900 

208,300 

Feb. 

391,000 

2,490,000 

224,000 

49,000 

0 

29.000 

0 

394 

101,900 

22.000 

123,900 

Mar. 

912,000 

2,579,000 

250,000 

107,000 

0 

316,000 

0 

400 

104,200 

43,800 

148,000 

April 

457,000 

2,818,000 

247,000 

77,000 

7,000 

0 

4,000 

411 

109,000 

33,900 

142,900 

May 

413,000 

2,940,000 

276,000 

110,000 

10,000 

0 

17,000 

412 

117,509 

46.600 

164,100 

June 

247,000 

2,940,000 

282,000 

11,000 

12,000 

0 

0 

412 

124.209 

1,900     129,100 

July 

219,000 

2,882,000 

297,000 

35,000 

14,000 

0 

0 

408 

125.400 

14,800     140,200 

Aug. 

208,000 

2,755,000 

303,000 

43,000 

13,000 

0 

0 

402 

126.700 

17,900     144,600 

Sept. 

201,000 

2,004.000 

282,000 

44,000 

10,000 

0 

0 

394 

120.000 

18,800     138,800 

Oct. 

308,000 

2,469,000 

278,000 

121,000 

7,000 

0 

0 

388 

113.400 

49,200|    162,600 

Nov. 

368,000 

2,371,000 

264,000 

145,000 

5,000 

0 

0 

384 

110,300 

59,700     170,000 

Dec. 

697,000 

2,325,000 

271,000 

222,000 

0 

0 

0 

384 

109,400 

89,000l    198,400 

Total  or 
average 

5,720,000 

3,214,000 

1,238,000 

78,000 

1,228,000 

21,000 

398 

113.400 

42,900 

156,300 

1901 

Jan. 

895,000 

2,529,000 

239.000 

251,000 

0 

446,000 

0 

389 

97.400 

101,600 

199.000 

Feb. 

1,304,000 

2,488,000 

227.000 

223,000 

0 

801,000 

0 

386 

101.900 

99,400 

201,300 

Mar. 

749,000 

2,541,000 

251.000 

128,000 

0 

155,000 

0 

398 

104,200 

52,400 

156,600 

April 

382,000 

2,756,000 

249.000 

0 

7,000 

0 

0 

408 

109,000 

0 

109,000 

May 

411,000 

2,882,000 

276,000 

67,000 

10,000 

0 

0 

412 

117,500 

28,500 

146,000 

June 

240,000 

2,940,000 

282,000 

4,000 

12,000 

0 

0 

412 

124,200 

1,800 

126.000 

July 

218,000 

2,882,000 

297.000 

34,000 

14,000 

0 

0 

408 

125,400 

14.200 

139,600 

Aug. 

206,00C 

2,755,000 

303,000 

41.000 

13,000 

0 

0 

402 

126,700 

17,100 

143,800 

Sept. 

200,000 

2,604,000 

282,000 

43,000 

10,000 

0 

0 

394 

120,000 

18,200 

138,200 

Oct. 

215,000 

2,469,000 

278,000 

28,000 

7,000 

0 

0 

388 

113,400 

11,400 

124,800 

Nov. 

354,000 

2.371.000 

265,000 

103,000 

5,000 

0 

0 

383 

1 10,300 

42,500 

152.800 

Dec. 
Total  or 
average 

650,000 

2.352,000 

272,000 

252,000 

0 

0 

0 

383 

109,400 

100,600 

210.000 

6,724,000 

3,221,000 

1,174,000 

78,000 

1.402,000 

0 

397 

113,400 

40.400 

153,800 

1902 

Jan. 

227.000 

2,378.000 

240.000 

0 

0 

0 

0 

386 

97.400 

0 

97.400 

Feb. 

2.782,000 

2,366.000 

230,000 

176,000 

0 

2,175,000 

0 

381 

101,900 

77,100 

179,000 

Mar. 

1.115.000 

2,.566.000 

251,000 

183,000 

0 

409,000 

0 

398 

104,200 

75,300 

179,500 

April 
May 

891,000 

2,838,000 

249.000 

187,000 

7,000 

0 

346,000 

408 

109,000 

81, 5(H) 

190,500 

7(i5,(K)0 

2,940,000 

278,000 

216,000 

10,000 

0 

201,000 

409 

117,500 

91,100 

208,900 

June 

407,000 

2,940,000 

282,000 

164,000 

12,000 

0 

7,000 

410 

121,200 

71,700 

195,900 

July 

254.000 

2,882,000 

298,000 

69.00C 

14.000 

0 

0 

406 

125,400 

29,000 

154,400 

Aug. 

234.000 

2,755,000 

304.000 

68.000 

13.000 

0 

0 

400 

126,700 

28,400 

155,100 

Sept. 

184.000 

2,604,000 

282,000 

27.000 

10,000 

0 

0 

394 

120,000 

11.400 

131,400 

Oct 

235.000 

2,469,000 

278,000 

48,000 

7.000 

0 

0 

388 

113.400 

19,500 

132.900 

Nov. 

829.000 

2,371,000 

258,000 

190,000 

5.000 

0 

0 

396 

110.300 

81,100 

191.400 

Deo. 
Total  or 
average 

762.000 

2,747.000 

264,000 

241,000 

0 

352.000 

0 

400 

109.400 

100,600 

210.000 

8,685,000 

3.214.000 

1,569.000 

78.000 

2.936.000 

614.000 

398 

113.400 

56.300 

168.700 

'Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE    CONTROL   OF    FLOODS   BY   RESERVOIRS. 


269 


RESERVOIR  ON  SACRAMENTO  RIVER. 

MARILY  FOR  POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  4,  page  114.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.P.  =0.80. 


Flood  control 

holding  maximum  space  required 

(454,000  at 

.-ft.)  In  reserve 

throughout  flood  season 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Stage  of 

Power  draft 

Release 

Average  powtr 

yield 

Year  and 

reservoir 

through  turbines  in 

through 

Waste 

Average 

in  kilowatts 

month 

at 

acre-feet 

Evapora- 

flood 

over 

(Load  factor= 

0.75) 

beginning 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

of 

1 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-feet 

*Primary 

Second- 
ary 

Total 

1 

1899 

2,07.5,000 

235.000 

° 

0 

0 

0 

380 

94,100 

0 

9,,  100 

Jan. 

2,445,000 

217,000 

!  ■       0 

0 

0 

0 

392 

98,500 

0 

98,500 

Feb. 

2,481,000 

247,000 

1      212,000 

0 

i      436,000 

0 

388 

100,500 

85,900 

186,400 

Mar. 

2,486,000 

1      247,000 

I        59,000 

1         7,000 

1        19,000 

0 

393 

105,300 

24,400 

129,700 

April 

2,610,000 

'      272.000 

0 

9,000 

0 

0 

399 

113,300 

0 

113,bOO 

May 

2,659,000 

278.000 

0 

11,000 

0 

0 

400 

119,700 

0 

119,700 

June 

2,672,000 

291,000 

0 

14,000 

0 

0 

400 

121,100 

0 

121,100 

July 

2,607,000 

230.000 

57.000 

:        12,000 

0 

0 

394 

122.300 

23,400 

145,700 

Aug. 

2,466,000 

276,000 

40,000 

9,000 

0 

0 

388 

115.800 

16,800 

132,600 

Sept. 

2,338,000 

I      272.000 

65,000 

'         7.000 

0 

0 

382 

109,500 

26,100 

!      135,600 

Oct. 

2,246,000 

258,000 

197,000 

4,000 

0 

0 

379 

106,500 

80,700 

187,200 

Nov. 

2,432,000 

!      260,000 

257,000 

0 

86,000 

0 

38S 

105,600 

104,400 

210,000 

Dec. 
Total  or 
average 

3,149,000 

887,000 

73,000 

541000 

0 

390 

109,400 

30,400 

139,800 

2,475,000 

230,000 

277,000 

0 

781,000 

0 

391 

94,100 

112,900 

207,000 

1900 

Jan. 

2,486,000 

217,000 

144,000 

0 

30,000 

0 

391 

98,500 

64,900 

163,400 

Feb. 

2,486,030 

247,000 

257,000 

0 

408,000 

0 

388 

100,500 

104,200 

204,700 

Mar. 

2,486,000 

247,000 

49,000 

7,000 

3,000 

0 

395 

105,300 

20,700 

126,000 

April 

2,637,000 

271,000 

0 

10,000 

0 

0 

403 

113,300 

0 

113,-300 

May 

2,769,000 

275,000 

0 

11,000 

0 

0 

404 

119,700 

0 

119,700 

June 

2,730,000 

290,000:        35,000 

14,000 

0 

0 

401 

121,100 

14,700 

135,800 

July 

2,610,000 

296,000 

44,000 

12,000 

0 

0 

394 

122.300 

18,100 

140,400 

Aug. 

2.466,000 

276,000 

44,000 

9,000 

0 

0 

388 

115,800 

18,500 

134,300 

Sept. 

2,338,000 

272,000 

121,000 

7,000 

0 

0 

382 

109,500 

48,500 

158,000 

Oct. 

2,246,000 

259,000 

151,000 

4,000 

0 

0 

377 

106.500 

61,900 

168,400 

Nov. 

2,200,000 

266,000 

251,000 

0 

0 

0 

377 

105,600 

99,200 

2(M,800 

Dec. 
Total  or 
average 

3,146,000 

1,373,000 

74,000 

1,222,000 

0 

391 

109,400 

47,100 

156,500 

2,380,000 

232,000 

287,000 

0 

270,000 

0 

387 

94,100 

115,900 

210,000 

1901 

Jan. 

2,486,000 

220,000 

239,000 

0 

845,000 

0 

385 

98,500 

106,800 

205,300 

Feb. 

2,486,000 

247,000 

261,000 

0 

241000 

0 

388 

100,500 

106,000 

206,500 

Mar. 

2,486,000 

248,000 

36,000 

7,000 

0 

0 

393 

105,300 

15.400 

120,700 

April 

2,577,000 

273,000 

0 

9,000 

0 

0 

400 

113,300 

0 

113,300 

May 

2,706,000 

278,000 

0 

11,000 

0 

0 

401 

119,700 

0 

119,700 

June 

2,657,000 

292,000 

0 

14,000 

0 

0 

398 

121.100 

0 

121.100 

July 

2,560,000 

298,000 

0 

12,000 

0 

0 

394 

122,300 

0 

122,300 

Aug. 

2,465,000 

269,000 

49,000 

9,000 

0 

0 

388 

115,800 

20,600 

136,400 

Sept. 

2,338,000 

272,000 

28,000 

7,000 

0 

0 

382 

109,500 

11,300 

120,800 

Oct. 

2,246,000 

259,000 

106,000 

4,000 

0 

0 

377 

106,500 

43,300 

149,800 

Nov. 

2,231,000 

266,000 

264,000 

0 

0 

0 

377 

105,600 

104,400 

210,000 

Dec. 
Total  or 
average 

3,154,000 

1.270,000 

73,000 

1,356,000 

0 

389 

109,400 

43,400 

152,800 

2,251,000 

236,000 

0 

0 

0 

0 

379 

94,100 

0 

91,100 

1902 

Jan. 

2,242,000 

223,000 

183,000 

0 

2,132,000 

0 

378 

98,500 

79.800 

178,300 

Feb. 

2,486,000 

248,000 

272,000 

0 

595,000 

0 

386 

100,500 

109.500 

210,000 

Mar. 

2,486,000 

245,0001      171,000 

7,000 

95,000 

0 

399 

105,300 

73,500 

178,800 

April 

2,859,000 

267,000 

229,000 

10,000 

0 

178,000 

409 

113,300 

96,700 

210,000 

May 

2,940,000 

273,000 

207,000 

12,000 

0 

7,000 

410 

119,700 

90.300 

210,090 

June 

2,848,000 

290,000 

188,000 

14,000 

0 

0 

402 

121,100 

78,800 

199,900 

July 

2,610,000 

298,000 

68,000 

12,000 

0 

0 

392 

122,300 

27,800 

150,100 

Aug. 

2,466,000 

276.000 

27.000 

9,000 

0 

0 

387 

115,800 

11,400 

127,200 

Sept. 

2,338,000 

272,000 

48.000 

7,000 

0 

0 

382 

109,500 

19,200 

128,700 

Oct. 

2,246,000 

255.000 

202,000 

4,000 

146,000 

0 

385 

106,500 

84,.300; 

190,809 

Nov. 

2,468,000 

260,000 

258,000 

"i 

226,000 

0 

388 

105,600 

101,4001 

210,000 

Dec. 
ToUl  or 
average 

3,143,0001 

1,853,000 

75,000  j 

3, 194 ,000 1 

185,000 

391 

109,400 

64,500 

173,900 

270 


WATER  RESOURCES  OF    CALIFORXIA. 


TABLE  4a  (Continued).     KENNETT 

COMPARISON  OF  WATER  AND  POWER  YIELD.  OPERATING  PRI 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 
Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Esti- 

Maximum reservcir  space 

required  454,000  ac 

ft. 

mated 
run-off 

Year  and 

at 

Stage  of 

Power  draft 

Release 

Average  power 

yield 

month 

dam 

reservoir 

through  turbines  in 

through 

'o"r^     Average 

in  kilowatt 

s 

site 

at 

acre-feet 

Evapora- 

flood 

(Load  factor=0.75) 

in 
acre-feet 

jeginning 
of 

tion  in 
acre-feet 

control 
outlets 

spillway  i  J^T:^ 

in 

feet 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-feet 

•Primary 

Second- 
ary 

Total 

1903 

Jan. 

1,113,000 

2,652,000 

240,000 

264.000 

0 

772,000 

0 

388 

97.400 

106,900 

204,300 

Feb. 

633,000 

2,489,000 

226,000 

222,000 

0 

126,000 

0 

390 

101,900 

100.100 

202,000 

Mar. 

1,339,000 

2,548,000 

253,000 

242,000 

0 

580,000 

0 

394 

104,230 

99,600 

203,800 

April 

765,000 

2,812,000 

249,030 

225,000 

7.000 

46,000 

110,000 

408 

109,000 

98,100 

207,100 

May 

458,000 

2,940,000 

276,000 

152,000 

10,000 

0 

20,000 

412 

11 7,  .500 

64,700 

182,200 

.Tunc 

278,000 

2,940,000 

282,000 

42,000 

12,000 

0 

0 

412 

124,200 

18.300 

142,500 

.luly 

231,000 

2,882,000 

297,000 

47,000 

14,000 

0 

0 

408 

125,400 

19.800 

145,200 

Aug. 

204,000 

2,755,000 

303,000 

39,000 

13,000 

0 

0 

402 

126,700 

16,300 

143,000 

Sept. 

174.000 

2,604,000 

282,000        17,0001 

10,000 

0 

0 

394 

120,000 

7,200 

127,200 

Oct. 

199,000 

2,469,000 

278.000 

12,000 

7,000 

0 

0 

388 

113,400 

4.800 

118,200 

Nov. 

924,000 

2,371,000 

261,000 

156,000 

5.000 

0 

0 

390 

110,300 

65.600 

175,900 

Dec. 

530,000 

2,873,000 

263,000 

229,000 

0 

310,000 

400 

109,400 

95,300 

204,700 

Total  or 
average 

6,848.000 

3,210,000 

1.647,000 

78.000 

1.834.000 

130.000 

399 

113,400 

57.809 

171,200 

1904 

Jan. 

473,000 

2,601,000 

238,000 

232,000 

0 

83,000 

0 

392 

97,400 

94.500 

191.900 

Feb. 

1,742,000 

2,521,000 

236,000 

165,000 

0 

1,332.000 

0 

386 

98,400 

70.500 

168.900 

Mar. 

2,877,000 

2,530,000 

256,000 

262,000 

0 

2.031.000 

0 

387 

101,200 

105,800 

210,000 

.\pril 

1,467,000 

2,858.000 

250,000 

234,000 

7,000 

146.000 

748.000 

405 

109,000 

101,000 

210,000 

May 

914,000 

2,940,800 

279,009 

220,000 

10,000 

0 

405.000 

406 

117,500 

92,500 

210,000 

June 

505,000 

2,940,000 

283.000 

196,000 

12,000 

0 

48.000 

410 

124,200 

85,800 

210,000 

July 

377,000 

2,906,000 

298.000 

201,000 

14,000 

0 

0 

406 

125,400 

84,600 

210,000 

Aug. 

282,000 

2,770,000 

304,000 

131,000 

13,000 

0 

0 

400 

126,700 

54,600 

181,300 

Sept. 

271,000 

2.604,000 

282,000 

114,000 

10,000 

0 

0 

393 

120,000 

48,300 

168,300 

Oct. 

491,000 

2.469.000 

276.000 

201,000 

7,000 

0 

0 

.391 

113.400 

81,900 

195,300 

Nov. 

379,000 

2.476,000 

263,000 

2U,000 

5,000 

0 

0 

386 

110,300 

99,700 

210,000 

Dec. 

600,000 

2.346.000 

273.000 

252,000 

0 

0 

0 

381 

109.400 

100,600 

210.000 

Total  or 
average 

. 

10,378,000 

3,238.000 

2,449,000 

78,000 

3,592,000 

1,201,000 

395 

113.000 

85.100 

198.100 

1905 

.Ian. 

1,371,000 

2.421,000 

238.000 

179,000 

0 

743,000 

0 

391 

97.400 

72,600 

170,000 

Feb. 

1,027,000 

2,632,000 

224.000 

229,000 

0 

607,000 

0 

393 

101,900 

103.600 

205,500 

Mar. 

1,335.000 

2,599,000 

251.000 

238,000 

0 

524,000 

0 

398 

104,200 

98.400 

202.600 

April 
May 

753,000 

2,921,000 

249.000 

231,000 

7,000        29,000 

218,000 

408 

103,000 

101.000 

210,000 

560.000 

2,940,000 

276,000 

207,000 

10.000 

0 

67,000 

411 

117,500 

87,600 

205,100 

June 

365,000 

2,940.000 

283,000 

128,000 

12.000 

0 

0 

410 

124,200 

56,100 

180,300 

July 

269,000 

2,882,000 

298,000 

84,000 

14,000 

0 

0 

407 

125,400 

35.500 

160,900 

Aug. 

236.000 

2,755,000 

304,000 

70,000 

13.000 

0 

0 

400 

126,700 

29,200 

155,900 

Sept. 

208.000 

2,601,000 

282,000 

51,000 

10.000 

0 

0 

394 

120,000 

21,700 

141,700 

Oct. 

221,000 

2,469,000 

278,000 

34,000 

7,000 

0 

0 

388 

113,400 

13.800 

127,200 

Nov. 

22D,000 

2,371,000 

264,000 

53.000 

5.000 

0 

0 

b84 

110,300 

21.000 

132,200 

Dec. 

249,000 

2,278,000 

270.000 

0 

0 

0 

0 

380 

109.400 

0 

109,400 

Total  or 
average 

6,823,000 

3.217.000 

1.504.000 

78.000 

1,903.000 

285.000 

397 

113.400 

53.100 

166,500 

906 

Jan. 

851,000 

2.2.57,000 

239,000 

52,000 

0 

109,000 

0 

390 

97,400 

21,600 

119,000 

Feb. 

872,00(1 

2.708.000 

222.000!      141,000 

0      611,000 

0 

398 

101,000 

63,700 

16.5,600 

Mar. 

l,t>ir),n()o  s.tinii.odo:    :>53,oi)(i     2tl.oo() 

0      924.000 

0'      394 

104.200 

98,900 

203,100 

April 
May 

!i'.l,i,(H)(l,  2. S:t  1.0(H);      249.(»()0i      2:i2,(K)0 

7.(K)0:      136,000 

2t)o,000;      408 

109,000 

101,000 

210,000 

817.(»')0;  2.il40.(HK)      278.000;      220.00(1 

10.000 

0 

309,000 

408 

117,.500 

92.500 

210,000 

June 

756.(MK) 

2,940,(H1(I,     284,000!      196,000 

12.000 

0 

265,000 

409 

124.200 

85,800 

210,000 

July 

302.000 

2,93',t,l)O0      297,000       201,000 

14.000 

0 

0 

408 

12.5,400 

84,600 

210,000 

Aug. 

280.0(M) 

2.78'.t,0(MI      304.000       148,000 

13.000 

0 

0 

400 

126.700 

61,700 

188,400 

Sept. 

247.00(1 

2.60t.0(H)      283.000        89,000 

10,000 

0 

0 

394 

120.000 

37,800 

l,=7,8O0 

Oct. 

251,0(K) 

2.469.{KK):     278.000|       64,000 

7,000 

0 

0 

388 

113,400 

26,100 

139,500 

Nov. 

256,000 

2.371,000 

205,000        79,000 

5,000 

0 

0 

383 

110,300 

32.800 

143,100 

Dec. 

648,000 

2.278,000 

272,000|      186,000 

0 

0 

0 

382 

109,400 

74,300 

183,700 

ToUl  or 
average 

7.981.000 

3,224,000j  1.849.000 

78,000 

1.780.000 

839,000 

397 

113,400 

65.100 

178,500 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS.  271 

RESERVOIR  ON  SACRAMENTO  RIVER. 

MARILY  FOR  POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  4,  page  114.) 

Installed  capacity  of  power  plant  400,000  k.v.a.     P.F.  =  0.80. 


Flood  control, 

liolding  maximum  space  required  (454,000  ac. 

-ft.)  in  reserve 

throughout  flood  season 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec 

.-ft. 

Stage  of 

Power  draft 

Release 

Average  power  yield 

reservoir 

through  turbines  in 

through 

Waste 

Average 

n  kilowatts 

Year  and 

at  _ 

acre-feet 

Evapora- 

flood 

over 

(Load  factor=fl 

.75) 

month 

beginning 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

of 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 

acre-feet 

acre-feet 

♦Primary 

Second- 
ary 

Total 

1903 

2,486,000 

231,000 

222,000 

0 

660,000 

0 

387 

94,100 

89.500 

183.600 

Jan. 

2,486.000 

219,000 

249,000 

0 

165,000 

0 

386 

98,500 

111, .500 

210,000 

Feb. 

2,486,000 

248,000 

270,000 

0 

821,000 

0 

386 

100,500 

109,509 

210,000 

Mar. 

2,486,000 

246,000 

99,000 

7,000 

151,000 

0 

396 

105,300 

41,900 

147,200 

April 

2,748,000 

270,000 

145,000 

10,000 

0 

(1 

405 

113,300 

60,600 

173,900 

May 

2,781,000 

275,000 

43,000 

11,000 

0 

0 

405 

119,700 

18,600 

138,.300 

June 

2,730,000 

290,000 

47,000 

14,000 

0 

0 

401 

121,100 

19,600 

140,700 

July 

2,610,000 

296,000 

40,000 

12,000 

0 

0 

394 

122,300 

16,500 

1.38,800 

Aug. 

2,466,000 

276,000 

17,000 

9,000 

0 

0 

388 

115,800 

7,100 

122,900 

Sept. 

2,338,000 

272,000 

12,000 

7,000 

0 

0 

382 

109,500 

4,800 

114,300 

Oct. 

2,246,000 

257,000 

166,000 

4,009 

257,000 

0 

380 

106,500 

68,200 

174,700 

Nov. 

2,486,000 

260,000 

257,000 

0 

35,000 

0 

389 

105,600 

104,400 

210,000 

Dec. 
Total  or 

3,140,000 

1,567,000 

74,000 

2,089,000 

0 

392 

109,400 

54,100 

163,500 

average 

2.464.000 

230.000 

202,000 

0 

19,000 

0 

390 

94,100 

82,300 

176,400 

1904 

Jan. 

2.486,000 

228,000 

209,000 

0 

1,305,000 

0 

384 

95,100 

89,400 

184,500 

Feb. 

2.-186,000 

252,000 

276,000 

0 

2,349,000 

0 

378 

100,500 

109,500 

210,000 

Mar. 

2,486,000 

245,000 

196,000 

7,000 

257,000 

308,000 

398 

105,300 

84,000 

189,300 

April 

2.940,000 

268,000 

228,000 

10,000 

0 

408,000 

408 

113,300 

96,700 

210,000 

May 

2,940,000 

273,000 

206,000 

12,000 

0 

48,000 

410 

119,700 

90,300 

210,000 

June 

2,906,000 

288,000 

211,000 

14,000 

0 

0 

406 

121,100 

88,900 

210,000 

July 

2,770,000 

265,000 

213,000 

13,000 

0 

0 

398 

122,300 

87,700 

210,000 

Aug. 

2,531,000 

276,000 

178,000 

10,000 

0 

0 

388 

115,800 

74,600 

190,400 

Sept. 

2,338,000 

271,000 

252,000 

7,000 

0 

0 

382 

109,500 

100,500 

210,000 

Oct. 

2,299,000 

260,000 

249,000 

4,000 

0 

0 

376 

106,500 

101,500 

208,000 

Nov. 

2.165,000 

269,000 

259,000 

0 

0 

0 

372 

105,600 

101,500 

207,100 

Dec. 
Total  or 
average 

3,155,000 

2,679,000 

77,000 

3,930,000 

764,000 

391 

109,100 

92,300 

201,400 

2,237,000 

234,000 

158.000 

0 

730,000 

0 

384 

94,100 

63,600 

157.700 

1905 

Jan. 

2,486,000 

219,000 

251,000 

0 

557,000 

0 

386 

98,500 

111,500 

210,000 

Feb. 

2,480,000 

249,000 

272,000 

0 

814,000 

0 

385 

100,500 

109,500 

210,000 

Mar. 

2,486,000 

246,000 

107,000 

7,000 

128,000 

0 

396 

105,300 

45,600 

150,900 

April 

2,751,000 

270,000 

210.000 

10,000 

0 

0 

406 

113,300 

88,200 

201,500 

May 

2,821,000 

275,000 

170.000 

11,000 

0 

0 

404 

119,700 

73,800 

193,500 

June 

2,730,000 

231,000 

84,000 

14.000 

0 

0 

400 

121,100 

34,900 

156,000 

July 

2,610,000 

298,000 

70.000 

12.000 

0 

0 

394 

122,300 

28,800 

151,100 

Aug. 

2,406,000 

270.000 

51,000 

9.000 

0 

0 

387 

115,800 

21,400 

137,200 

Sept. 

2,338,000 

272,000 

34,000 

7,000 

0 

0 

382 

109,500 

13,700 

123,200 

Oct. 

2,246,000 

259,000 

53,000 

4,000 

0 

0 

378 

106,500 

21,800 

128,300 

Nov. 

2,159.000 

268,000 

65,000 

0 

0 

0 

372 

105,600 

25,500 

131,100 

Dec. 
Total  or 
average 

3,157,000 

1,525,000 

74,000 

2,229,000 

0 

390 

109,400 

52,800 

162,200 

2,075,000 

235.000 

109,000 

0 

96,000 

0 

380 

94,100 

44,400 

138,500 

1906 

Jan. 

2,486,000 

219,000 

214,000 

0 

439,000 

0 

387 

985,000 

95,800 

194,300 

Feb. 

2,486,000 

248,000 

273,000 

0 

1,101,000 

0 

384 

100.500 

109,500 

210,000 

Mar. 

2,510,000 

246,000 

145,000 

7,000 

278,000 

0 

397 

105.300 

61,500 

166,800 

April 

2,829,000 

268,000 

229,000 

10,000 1                0 

199,000 

409 

113,300 

96,700 

210,000 

May 

2,940,000 

273,000 

207,000 

12.000 1                0 

266,000 

410 

119,700 

90,300 

210,000 

June 

2,938,000 

287,000 

212.000 

14,000 

0 

0 

408 

121,100 

88,900 

210,000 

July 

2,787,000 

294.000 

211.000 

13,000 

0 

0 

398 

122,300 

87,700 

210,000 

Aug. 

2,549,000 

276,000 

172,000 

10,000 

0 

0 

388 

115,800 

72,200 

188,000 

Sept. 

2.338,000 

272.000 

64.000 

7,000 

0 

0 

382 

109,500 

25,700 

135,200 

Oct. 

2,246,000 

259,000 

80,000 

4,000 

0 

0 

378 

106.500 

32,900 

139,400 

Nov. 

2,159,000 

267,000 

215,000 

1           0 

0 

0 

375 

105.600 

84.700 

190,300 

Dec. 
Total  or 
average 

3,144,000 

2,131,000 

77,000    1,914,000 

465,000 

391 

109,400 

74,100 

183,500 

272 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  4a  (Continued).     KENNETT 

COMPARISON  OF  WATER  AND  POWER  YIELD,  OPERATING  PRI 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 
Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Esti- 

Max 

mum  reservoir  space 

required  454,000  ac 

-ft. 

mated 
run-off 

Year  and 

at 

Stage  of 

Powe 

draft 

Release 

.\verage  power  yield 

month 

dam 

reservoir 

through  turbines  in 

through 

Waste 

Average 

in  kilowatts 

site 

at 

acre-feet 

Evapora- 

flood 

over 

(Load  factor=0.75) 

in 
acre-feet 

beginning 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

of 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-feet 

•Primary 

Second- 
ary 

Total 

1907 

Jan. 

936,000 

2,488,000 

239,000 

247,000 

0 

430,000 

0 

389 

97,400 

100,300 

197,700 

Feb. 

1,636,000 

2,488,000 

229,000 

243,000 

0 

1,122,000 

0 

384 

101,900 

108.100 

210,000 

Mar. 

2,115,000 

2,o30,000i     2.54,000 

259.000 

0 

1,314,000 

0 

392 

104,200 

105,800 

210,000 

April 

1,250,000 

2.818.000  249.000 

2.940.0001  278,000 

234.000 

7,000 

178,000 

460,000 

406 

103,000 

101,000 

210,000 

May 

646,000 

219.000 

10,000 

0 

139,000 

408 

117,500 

92.500 

210,000 

June 

421,000 

2,940,000      282,000 

179.000 

12,000 

0 

6,000 

410 

124,200 

78.200 

202,400 

July 

334,000 

2,882,000|     2.)8.000 

149.000 

14,000 

0 

0 

406 

12.5,400 

62.600 

188,090 

Auc 

2i)l,000 

2.755,000:     304,000 

125,000 

13,000 

0 

0 

400 

126,700 

52,000 

178,700 

Sept. 

2.52,000 

2,604,000 

282.000 

95,000 

10,000 

0 

0 

394 

120,000 

40,300 

160,300 

Oct. 

261,000 

2,469,000 

278,000 

74,000 

7,000 

0 

0 

388 

113,400 

30,100 

143,500 

Nov. 

256,000 

2,371,000 

264.000 

80,000 

5,000 

0 

0 

384 

110,300 

33,300 

143.600 

Dec. 

479,000 

2,278,000 

273,000 

138,000 

0 

0 

0 

380 

103.400 

55,100 

164.500 

Total  or 
average 

8,877,000 

3,230,000 

2,042,000 

78,000 

3,044,000 

605,000 

395 

113,400 

71,400 

184,800 

1908 

Jan. 

904,000 

2,346,000 

237,000 

94,000 

0 

264,000 

0 

394 

97,400 

38,300 

135,700 

Feb. 

970,000 

2,655,000 

234,000 

210,000 

0 

629,000 

0 

388 

98,400 

90,800 

189,200 

Mar. 

669,000 

2,552,000      250,000 

88,000 

0 

37,000 

0 

401 

104,200 

36,300 

140,.50O 

April 

527,000 

2,846,000      247,000 

134,000 

7,000 

0 

45,000 

411 

109,000 

58,300 

167,300 

May 

492,000 

2,940,000      276,000 

187,000 

10,000 

0 

19,000 

411 

117,500 

79.600 

197,100 

June 

340.000 

2,940,000      283,000 

103,000 

12,000 

0 

0 

410 

124,200 

45,100 

169.300 

July 

260.000 

2,882,000      298,000 

75,000 

14,000 

0 

0 

407 

125,400 

31.600 

157,000 

Aug. 

223.000 

2,755,000 

304,000 

63,000 

13,000 

0 

0 

400 

126,700 

26.200 

152,900 

Sept. 

205,000 

2,604,000 

282,000 

48,000 

10,000 

0 

0 

304 

120,000 

20,400 

140.400 

Oct. 

235,000 

2,469,000 

278,000 

48,000 

7,000 

0 

0 

388 

113.400 

19,500 

132,900 

Nov. 

257,000 

2,371,000 

264,000 

81,000 

5,000 

0 

0 

384 

110,300 

33,800 

144,100 

Dec. 
Total  or 
average 

267,000 

2,278,000 

273,000 

15.000 

0 

0 

0 

380 

109,400 

5,900 

115,300 

5,355,000 

3,226,000 

1,146,000 

78.000 

930,000 

64,000 

398 

113,000 

40,200 

153.200 

1909 

Jan. 

3,260.000 

2,257,000 

242,000 

218,000 

0 

2,551,000 

0 

383 

97,400 

87.100 

184,500 

Feb. 

2,526,000 

2,506,000 

227,000 

242,000 

0 

1,938,000 

0 

386 

101,900 

108,100 

210,000 

Mar. 

977,000 

2,625,000 

249,000 

197,000 

0 

247,000 

0 

401 

104.200 

81,700 

185,900 

April 
May 

758,000 

2,909,000 

249,000 

229,000 

7,000 

10,000 

230,000 

409 

109,000 

100,100 

209,100 

581,000 

2,940,000 

276.000 

216,000 

10,000 

0 

79,000 

410 

117,500 

91,500 

209,000 

June 

410,000 

2,940,000 

282,000 

171,000 

12,000 

0 

3,000 

410 

124,200 

74,900 

199,100 

July 

308,000 

2,882.000 

298,000 

123,000 

14,000 

0 

0 

406 

125,400 

51,700 

177,100 

Aug. 

264,000 

2,755,000 

304,000 

98,000 

13,000 

0 

0 

400 

126,700 

40,900 

167.600 

Sept. 

246,000 

2,604,000 

282,000 

89,000 

10,000 

0 

0 

394 

120,000 

37,800 

157,800 

Oct. 

284,000 

2,469.000 

278.000 

97,000 

7,000 

0 

0 

388 

113,400 

39,400 

152,800 

Nov. 

538,000 

2,371.000 

264,000 

174,000 

5,000 

0 

0 

384 

110,300 

72,500 

182,800 

Dec. 
Total  or 
average 

721,000 

2,466.000 

268.000 

245,000 

0 

39,000 

0 

395 

109.400 

100,600 

210,000 

10,871.000 

3,217,000 

2,099,000 

78,000 

4,785,000 

312,000 

397 

113,400 

73,600 

187,000 

1910 
Jan. 

708,000 

2,637,000 

235.000 

139,000 

0 

327,000 

0 

398 

97,400 

57,000 

151,400 

Fob. 

847,000 

2.644,000]     221,000 

138,000 

0 

358,000 

0 

399 

101,900 

62.900 

164,800 

Mar. 

1,239,000 

2.774,000      247,000 

239.000 

0 

351,000 

236.000 

406 

104,200 

100,400 

204,600 

April 
May 

665,000 

2,940,000 

249,000 

232,000 

7,000 

0 

177,000 

408 

109,000 

101.000 

210,000 

415.000 

2,940,000 

276,000 

128,000 

10,000 

0 

1,000 

412 

117,.500 

54,400 

171,900 

June 

2S2,00U 

2,910,000 

282,000 

46,000 

12,000 

0 

0 

412 

124,200 

20,100 

144,300 

July 

251.000 

2.882,000 

207,000 

70,000 

14,000 

0 

0 

408 

125,400 

29,400 

1.54,800 

Aug. 

236.000 

2,755,000      301,000 

70.000 

13.003 

0 

0 

400 

126,700 

23.200 

155,900 

Sept. 

214,000 

2,604,000      282,000 

57.000 

10.000 

0 

0 

394 

120,000 

24,200 

144,200 

Oct. 

231,000 

2,469,000      278.000 

44.000 

7,000 

0 

0 

388 

113.400 

17,900 

131,300 

Nov. 

274.000 

2.371,000 

265,000 

97,000 

5,000 

0 

0 

383 

110,300 

40,300 

150,600 

Dec. 
Total  or 
average 

436,000 

2,278.000 

274,000 

183,000 

0 

0 

0 

380 

109,400 

73,000 

182,400 

5,801,000 

3,210,000 

1,443,000 

78.000 

1,036,000 

414,000 

399 

113,400 

50.800 

164,200 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


273 


RESERVOIR  ON  SACRAMENTO  RIVER. 

MARILY  FOR  POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  4,  page  114.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.F.=0.80. 


Flood  control, 

holding  maximum  space  required  (454,000  ac 

.-ft.)  In  reserve 

throughout  flood  season 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Stage  of 

Power  draft 

Release 

Average  power 

yield 

Year  and 

reservoir 

through  turbines  in 

through 

Waste 

Average 

in  kilowatis 

month 

at 

acre-feet 

Evapora- 

flood 

over 

(Load  factor= 

0.75) 

beginning 

tion  in 
acre-ieet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

of 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-feet 

*Prunary 

Second- 
ary 

Total 

1907 

2.325,000 

231,000 

249,000 

0 

295,000 

0 

388 

94,100 

100,900 

195,000 

Jan. 

2.486,000 

221,000 

252,000 

0 

1,163,000 

0 

383 

98,500 

111,500 

210,000 

Feb. 

2,486,000 

249,000 

273,000 

0 

1,593,000 

0 

383 

100,500 

109,500 

210,000 

Mar. 

2,486,000 

244,000 

196,000 

7,000 

250,000 

93,000 

400 

105.300 

84,000 

189,300 

April 

2,940,000 

267,000 

229,000 

10,000 

0 

140,000 

410 

113,.300 

96,700 

210,000 

May 

2,940,000 

273,000 

207,000 

12,000 

0 

0 

409 

119,700 

90,300 

210,000 

June 

2,869,000 

289,000 

213,000 

14,000 

0 

0 

404 

121,100 

88,900 

210,000 

July 

2,687,000 

296,000 

203,000 

13,000 

0 

0 

394 

122,300 

83,600 

205,900 

Aug. 

2.466,000 

277,000 

94,000 

9  000 

0 

0 

386 

115,800 

39,300 

155,100 

Sept. 

2.338,000 

272,000 

74.000 

7.000 '                0 

0 

382 

109,500 

29,700 

139,200 

Oct. 

2,246,000 

259,000 

80,000 

4,000 

0 

0 

378 

106,500 

32,900 

139,400 

Nov. 

2,159,000 

269,000 

194,000 

0 

0 

0 

374 

105,600 

76,200 

181,800 

Dec. 
Total  or 
average 

3,147,000 

2,264,000 

76,000 

3,307,000 

233.000 

391 

109,400 

78,500 

187,900 

2,175,000 

232,000 

121,000 

0 

240,000 

0 

386 

94,100 

48,500 

142,600 

1908 

Jan. 

2,486,000 

226,000 

258,000 

0 

486,000 

0 

388 

95,100 

111,600 

206,700 

Feb. 

2,486,000 

248,000 

269,000 

0 

152,000 

0 

389 

100,500 

109,400 

209,900 

Mar. 

2,486,000 

247,000 

49,000 

7,000 

0 

0 

395 

105,300 

20,700 

126,000 

April 

2,710,000 

270,000 

141,000 

10,000 

0 

0 

405 

113,300 

59,000 

172,300 

May 

2,781,000 

275,000 

104,000 

11,000 

0 

0 

404 

119.700 

45,100 

164.800 

June 

2,730,000 

291,000 

75,000 

14,000 

0 

0 

400 

121,100 

31,200 

152.300 

July 

2,610,000 

298,000 

63,000 

12,000 

0 

0 

394 

122,300 

25.900 

148,200 

Aug. 

2,466,000 

276,000 

48,000 

9,000 

0 

0 

387 

115,800 

20,100 

135,900 

Sept. 

2,338,000 

272,000 

48,000 

7,000 

0 

0 

382 

109,500 

19,200 

128,700 

Oct. 

2,246,000 

259,000 

81,000 

4,000 

0 

0 

378 

106,500 

33,300 

139,800 

Nov. 

2,159,000 

269,000 

82,000 

0 

0 

0 

372 

105,600 

32,300 

137,900 

Dec. 
Total  or 
average 

3,164,000 

1,339,000 

74,000 

878,000 

0 

390 

109,100 

46,200 

155.300 

2,075,000 

236,000 

226,000 

0 

2,387,000 

0 

378 

04,100 

89,700 

183,800 

1909 

Jan. 

2,486,000 

222,000 

253,000 

0 

2,051,000 

0 

380 

98,500 

111,500 

210.000 

Feb. 

2,486,000 

248,000 

273,000 

0 

456,000 

0 

386 

100,500 

109,500 

210,000 

Mar. 

2,486,000 

246,000 

123,000 

7,000 

77,000 

0 

397 

105,300 

52,500 

157,800 

April 

2,789,000 

269,000 

230.000 

10,000 

0 

0 

406 

113,300 

96,700 

210,000 

May 

2,861,000 

275,000 

208,000 

12,000 

0 

0 

406 

119,700 

90,300 

210,000 

June 

2,776,000 

290,000 

170,000 

14,000 

0 

0 

400 

121,100 

70,800 

191,900 

July 

2,610,000 

298,000 

98,000 

12,000 

0 

0 

394 

122,300 

40,300 

162,600 

-^ug. 

2,466,000 

277,000 

88,000 

9,000 

0 

0 

386 

115.800 

36,800 

152,600 

Sept. 

2,338,000 

273,000 

96,000 

7,000 

0 

0 

381 

103,500 

38,400 

147,900 

Oct. 

2,246,000 

258,000 

179,000 

4,000 

0 

0 

378 

106,500 

73,600 

180,100 

Nov. 

2,343,000 

261,000 

258,000 

0 

84,000 

0 

387 

105,600 

104,400 

210,000 

Dec. 
Total  or 
average 

3,153,000 

2.202,000 

75,000 

5,055,000 

0 

390 

109,400 

76,100 

185,500 

2,461,000 

230,000 

229  000 

0 

224,000 

0 

389 

94,100 

93,800 

187,900 

1910 

,Ian. 

2,486,000 

219,000 

249,000 

0 

379,000 

0 

388 

98,500 

111,500 

210,000 

Feb. 

2,486,000 

248,000 

273,000 

0 

718,000 

0 

386 

100,500 

109,500 

210,000 

Mar. 

2,480,000 

246,000 

92,000 

7,000 

66,000 

0 

397 

105.300 

38,800 

144,100 

April 

2,740,000 

270.000 

94,000 

10,000 

0 

0 

404 

113,300 

39,400 

1,52,700 

May 

2,781,000 

275,000 

47,000 

11,000 

0 

0 

404 

119,700 

20,400 

140,100 

June 

2,730,000 

200,000 

70,000 

14,000 

0 

0 

400 

121,100 

29,200 

150,300 

July 

2,610,000 

298,000 

70,000 

12.000 

0 

0 

394 

122,300 

28,800 

151,100 

Aug. 

2,466,000 

270,000 !        57,000 

9,000 

0 

0 

387 

115,800 

23,900 

139,700 

Sept. 

2,338,000 

272,000.       '14,000 

7,000 

0 

0 

382 

109,500 

17.700 

127,200 

Oct. 

2,246,000 

259,000 

98,000 

4,000 

0 

0 

377 

103,500 

40,300 

146,800 

Nov. 

2.159,000 

268,000 

252,000 

0 

0 

0 

372 

105.600 

98,500 

204.100 

Dec. 
Total  or 
average 

3,151,000 

1,575,000 

74,000 

1,387.000 

0 

390 

109,400 

54.100 

163,500 

274 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  4a  (Continued).     KENNETT 

COMPARISON  OF  WATER  AND  POWER  YIELD,  OPERATING  PRI 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Esti- 

Maximum reservoir  space 

equired  454,000  ac.- 

ft. 

mated 

run-off 
at 

Year  and 

Stage  of 

Power  draft 

Release 

Average  power  yield 

month 

dam 

reservoir 

through  turbines  in 

through 

Waste 

Average 

in  kilowatts 

sitf 

at 

acre-feet 

Evapora- 

flood 

over 

(Load  factor= 

0.75) 

in 
acre-feet 

beginning 
of 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

head  iu 
feet 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-feet 

•Primary 

Second- 
ary 

Total 

1911 

Jan. 

700,000 

2,257,000 

241,000 

18.000 

0 

193,000 

0 

384 

97,400 

7,300 

104.700 

Feb. 

848,000 

2,505,000 

226,000 

168,000 

0 

377,000 

0 

389 

101,900 

75,000 

176.900 

Mar. 

1,278,000 

2,582,000 

253,000 

246,000 

0 

548,000 

0 

395 

101.200 

100.900 

205,100 

April 

062,000 

2,813.000 

249,000 

232,000 

7,000 

99,000 

248,000 

407 

109,000 

101,000 

210.000 

May 

671.000 

2.940.000 

278,000 

219.000 

10,000 

0 

164,000 

408 

117,500 

92,500 

210,000 

.lune 

431,000 

2,940,000 

282,000 

182,000 

12,000 

0 

13,000 

410 

124,200 

79,600 

203.800 

July 

287,000 

2,882,000 

298,000 

102,000 

14,000 

0 

0 

406 

125,400 

42.900 

168,3(J() 

Aug. 

244,000 

2.755,000 

304,000 

78,000 

13,000 

0 

0 

400 

126,700 

32.500 

159,200 

Sept. 

2.31,000 

2,604,000 

282,000 

74,000 

10,000 

0 

0 

394 

120,000 

30,700 

1.50,700 

Oct. 

246,000 

2,469,000 

278,000 

59,000 

7,000 

0 

0 

388 

113,400 

24.100 

137,500 

Nov. 

241,000 

2,371,000 

264,000 

65,000 

5,000 

0 

0 

384 

110,300 

26,900 

137,200 

Dec. 
Total  or 

244,000 

2,278,000 

273,000 

0 

0 

0 

0 

380 

109,400 

0 

109,400 

average 

6,383,000 

3,228,000 

1.443,000 

78,000 

1,217.000 

425,000 

306 

113.400 

50,800 

164,200 

1912 
Jan. 

517,000 

2,249,000 

239,000 

0 

0 

0 

0 

388 

97,400 

0 

97,400 

Feb. 

396,000 

2,527,000 

221,000 

0 

0 

0 

0 

399 

98,400 

0 

98,400 

Mar. 

635,000 

2,702,000 

246,000 

118,000 

0 

0 

33,000 

409 

104,200 

50,300 

154,500 

April 

487,000 

2,940.000 

247,000 

182,000 

7,000 

0 

51,000 

411 

109,000 

80,000 

189,000 

May 

714,000 

2,940,000 

277,000 

217,000 

10,000 

0 

210,000 

410 

117,500 

91,900 

209,400 

June 

405,000 

2,040,000 

282,000 

158.000 

12,000 

0 

11,000 

411 

124,200 

69,000 

193.200 

July 

274,000 

2,882,000 

298,000 

89,000 

14,000 

0 

0 

406 

125.400 

37,500 

162,900 

Aug. 

238,000 

2,755,000 

304,000 

72,000 

13,000 

0 

0 

400 

126,700 

30,000 

156.700 

Sept. 

242,000 

2,604,000 

282,000 

85,000 

10,000 

0 

0 

394 

120,000 

36,000 

156,000 

Oct. 

226,000 

2,469,000 

278,000 

39,000 

7,000 

0 

0 

388 

113.400 

15,900 

129,300 

Nov. 

4.32,000 

2,371,000 

264,000 

210,000 

5,000 

0 

0 

385 

110,300 

87,100 

197,400 

Dec. 
Total  or 
average 

369,000 

2,324,000 

273,000 

163,000 

0 

0 

0 

380 

109,400 

64.500 

173,900 

4,935,000 

3,211,000 

1,333,000 

78,000 

0 

305,000 

398 

113,000 

46,900 

159.900 

1913 

Jan. 

763,000 

2,257,000 

240,000 

111,000 

0 

137,000 

0 

386 

97.400 

45.000 

142.400 

Feb. 

387,000 

2,532,000 

222.000 

17,000 

(1 

0 

0 

399 

101,900 

7.600 

109.500 

Mar. 

441.00(1 

2,680.000 

247,000 

0 

0 

0 

0 

406 

104.200 

0 

104,200 

April 
May 

085,000 

2.874,000 

219,000 

200,000 

7,000 

0 

163.000 

409 

109,000 

87.600 

190,600 

.521,000 

2, '.140,00(1 

27(),0()0       201,000 

10,000 

0 

34,000 

411 

117,500 

85,500 

203,000 

June 

321,000 

2,940,000 

283.000         84.000 

12,000 

0 

0 

410 

124,200 

36,800 

161,000 

July 

21)3.000 

2,882,000 

298.000'        78,000 

14,000 

0 

0 

407 

125,400 

32,800 

158,200 

Aug. 

232.00(1 

2,7.55,(W() 

304.000 

60,000 

13,000 

0 

0 

400 

120,700 

27.600 

154,300 

Sept. 

rK),(K)(l 

2,691,001 

282,000 

33,000 

10,000 

0 

0 

394 

120,000 

14.000 

134,000 

Oct. 

202,000 

2,1(i9,0()Ot     278.000 

15,000 

7,000 

0 

0 

388 

113,400 

6.000 

119,400 

Nov. 

310,000 

2,371,000 

265,000 

105,000 

5,000 

0 

0 

383 

110,300 

43,600 

153,900 

Dec. 

696.000 

2,312.000 

272.000 

183,000 

0 

0 

0 

381 

109,400 

72,900 

182,300 

Total  or 
average 

5,017,000 

3,216,000 

1,093,000 

78,000 

137,000 

197,000 

398 

113,400 

38,500 

151,900 

1914 

Jan. 

2.707,000 

2,.553,000 

238,000 

258,000 

0 

2,075,000 

0 

392 

97,400 

105,200 

202,600 

Feb. 

1,3.59  000 

2,779.00( 

224.000 

2;;7,ooo 

0 

903,000 

0 

394 

101,900 

108,100 

210,000 

Mar. 

987,000 

2,774. 00( 

249,000 

240.000 

0 

374,000 

0 

402 

104,200 

99,600 

203,800 

Awil 
May 

i,i3;,()oo 

2,8'.I8,00( 

249.000;      231,(K)0 

7,000 

6,000 

602,000 

407 

109,000 

100,700 

209,700 

703,000 

2.940,()O( 

278.0001     220,000 

10,000 

0 

105,000 

408 

117,500 

92,.5()0 

2in.ono 

Juno 

452.000 

2,940,00( 

28H,(IOOi      196,000 

12,000 

0 

13,000 

410 

124,200 

85,800 

210.000 

July 

309,(H)0 

2,S8S,000;      298.000!       1.30,000 

14,000 

0 

0 

406 

125,400 

54,800 

180  200 

Aug. 

2I8,0(H) 

2.7.'')5.00(li     301.000!       82,000 

13,000 

0 

0 

400 

120,700 

34,100 

100,800 

Sept. 

225,(K)0|  2,(;0I,000|      2S2.()00;        68,000 

10,000 

0 

0 

394 

120,000 

28,800 

148,800 

Oct. 

269,(M)0 

2.46!I,0(M)      278.000,        82,000 

7,000 

0 

0 

388 

113,400 

33,200 

146,600 

Nov. 

252,000 

2,371,000 

205,000        75,000 

5,000 

0 

0 

383 

110.300 

31,100 

141,400 

Dec. 

347,000 

2,278,000 

273,000        95,000 

0 

0 

0 

380 

109.400 

37,900 

147,300 

Total  or 
average 

9,085,000 

3.221,000 

1,914,000 

78,000 

3,358,000 

810,000 

397 

113,400 

67.400 

180,800 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


275 


RESERVOIR  ON  SACRAMENTO  RIVER. 

MARILY  FOR  POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  4,  page  1 14.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.F.=0.80. 


Flood  control, 

holding  maximum  space  required  (454,000  ac 

-ft.)  in  reserve 

throughout  flood  season 

Ma.ximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Stage  of 

Powe 

r  draft 

Release 

Average  power 

yield 

Year  and 

reservoir 

through  turbines  in 

through 

Waste 

Average 

in  kilowatts 

month 

at 

acre 

-feet 

Evapora- 

flood 

over 

(Load  factor=: 

0.75) 

beginning 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

of 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 

acre-feet 

acre-feet 

*Primary 

Second- 
ary 

Total 

1911 

2,075,000 

237,000 

9,000 

0 

43,000 

0 

376 

94,100 

3,800 

97,900 

Jan. 

2,486,000 

220,000 

250,000 

0 

378,000 

0 

384 

98,500 

111,500 

210,000 

Feb. 

2,48r.,000 

249,000 

267,000 

0 

762,000 

0 

385 

100,500 

107,700 

208,200 

Mar. 

2,480,000 

246,000 

164,000 

7,000 

195,000 

0 

398 

105,300 

70,000 

175,300 

April 

2,836,000 

267,000 

229,000 

10,000 

0 

61,000 

410 

113,300 

96,700 

210,000 

May 

2,940,000 

273,000 

206,000 

12,000 

0 

13,000 

410 

119,700 

90,300 

210,000 

June 

2,867,000 

290,000 

212,000 

14,000 

0 

0 

402 

121,100 

88,900 

210,000 

July 

2,638.000 

298,000 

106,000 

12,000 

0 

0 

394 

122,300 

43,500 

165,800 

Aug. 

2,466,000 

277,000 

73,000 

9,000 

0 

0 

386 

115,800 

30,600 

146,400 

Sept. 

2,338,000 

272,000 

59,000 

7,000 

0 

0 

382 

109,500 

23,700 

133,200 

Oct. 

2,246,000 

259,000 

65,000 

4,000 

0 

0 

378 

106,500 

26,700 

133,200 

Nov. 

2,159,000 

269,000 

59,000 

0 

0 

0 

372 

105,600 

23,300 

128,900 

Dec. 
Total  or 
average 

3,157,000 

1,699,000 

V5,000 

1,378,000 

74,000 

390 

109,400 

59,300 

168,700 

2.075,000 

236,000 

0 

0 

0 

0 

378 

94,100 

0 

94,100 

1912 

Jan. 

2,.S50,000 

226,000 

40,000 

0 

0 

0 

390 

95,100 

17,700 

112,800 

Feb. 

2,486,000 

246,000 

269,000 

0 

120,000 

0 

390 

100,500 

109,500 

210,000 

Mar. 

2,486,000 

247,000 

37,000 

7,000 

0 

0 

395 

105,300 

15.400 

120,700 

April 

2,682,000 

269,000 

207,000 

10,000 

0 

0 

406 

113,300 

87,100 

200,400 

May 

2,910.000 

274,000 

206,000 

12,000 

0 

0 

408 

119,700 

90,300 

210,000 

June 

2,823,000 

290,000 

183,000 

14,000 

0 

0 

401 

121,100 

76,300 

197,400 

July 

2,610,000 

298,000 

72,000 

12,000 

0 

0 

393 

122,300 

29,600 

151.900 

Aug. 

2,466,000 

277,000 

84,000 

9,000 

0 

0 

386 

115,800 

35,100 

150,900 

Sept. 

2,338,000 

272,000 

39,000 

7,000 

0 

0 

382 

109,.500 

15,600 

125,100 

Oct. 

2,246,000 

258,000 

220,000 

4,000 

0 

0 

378 

106,500 

90,100 

196,600 

Nov. 

2,196,000 

268,000 

220,000 

0 

0 

0 

372 

105,600 

85,800 

191,400 

Dec. 
Total  or 
average 

3,161,000 

1,577,000 

75,000 

120,000 

0 

390 

100,100 

54,,500 

163,600 

2,077,000 

234,000 

98,000 

0 

22,000 

0 

381 

94,100 

39,800 

133,900 

1913 

.Tan. 

2,486,000 

218,000 

169,000 

0 

0 

0 

390 

98,500 

76,300 

174,800 

Feb. 

2,486,000 

245,000 

196,000 

0 

0 

0 

391 

100,500 

80,100 

180,600 

Mar. 

2,486,000 

246,000 

97,000 

7,000 

69,000 

0 

397 

105,300 

41,100 

146,400 

April 

2,752,000 

270,000 

212,000 

10,000 

0 

0 

404 

113,300 

89,000 

202,300 

May 

2,781,000 

276,000 

85,000 

11,000 

0 

0 

404 

119,700 

36,800 

156,50.) 

Juno 

2,730,000 

290,000 

79,000 

14,000 

0 

0 

400 

121,100 

32,900 

154,000 

July 

2,610,000 

298.000 

66,000 

12,000 

0 

0 

394 

122,300 

27,200 

149,500 

Aug. 

2,466,000 

276,000 

33,000 

9,000 

0 

0 

387 

115,800 

13,900 

129,700 

Sept. 

2,338,000 

272,000 

15,000 

7,000 

0 

0 

382 

100,500 

6,000 

115,500 

Oct. 

2,246,000 

259,000 

107,000 

4,000 

0 

0 

377 

106,500 

43,800 

150,300 

Nov. 

2,192,000 

268,000 

231,000 

0 

0 

0 

373 

105,600 

90,500 

196,100 

Dec. 
Total  or 
averiige 

3,152,000 

1,388,000 

74,000 

91,000 

0 

390 

109,400 

48,000 

157,400 

2,389,000 

235,000 

291,000 

0 

2,174,000 

0 

379 

94,100 

115,900 

210,000 

1914 

Jan. 

2,486,000 

220,000 

251,000 

0 

888,000 

0 

385 

98,500 

111,.500 

210,000 

Feb. 

2,486,000 

248,000 

273.00) 

0 

466,t00 

0 

386 

100,500 

10i),50U 

210.000 

Mar. 

2,486,000 

244,000 

190,000 

7,000 

107,000 

75,000 

400 

105,300 

81,800 

187,100 

April 

2,940,000 

267,000 

229,000 

10,000 

0 

197,000 

409 

113,300 

96,700 

210,000 

May 

2,940,000 

273,000 

207,000 

12,000 

0 

0 

409 

119,700 

90,300 

210,000 

June 

2,900,000 

288,000 

214,000 

14,000 

0 

0 

404 

121,100 

88,900 

210,000 

July 

2,693,000 

2it6,000 

166,000 

13,000 

0 

0 

395 

122,300 

68,400 

190,700 

Aug. 

2,466,000 

276,000 

68,000 

9,000 

0 

0 

387 

115,800 

28,500 

144,300 

Sept. 

2,338,000 

272,000 

82,000 

7,000 

0 

0 

382 

109,500 

32,900 

1 12,400 

Oct. 

2,246,000 

259,000 

76,000 

4,009 

0 

0 

378 

105,500 

31.300 

137,800 

Nov. 

2,159,000 

269,000 

162,000 

0 

0 

0 

372 

105,600 

63,700 

169,300 

Dec. 
Total  or 
average 

3,147,000 

2,209,000 

76,000 

3,695,000 

272,000 

390 

109,400 

76,500 

185,900 

276 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  4a  (Continued).     KENNETT 

COMPARISON  OF  WATER  AND  POWER  YIELD,  OPERATING  PRI 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Esti- 

Maximum reservoir  space  required  454,000  ac. 

ft. 

mated 

run-off 

at 

Year  and 

Stage  of 

Power  draft 

Release 

Average  power 

>ield 

moDtb 

dam 

reservoir 

through  turbines  in 

through 

Waste 

Average 

in  kilowatts 

site 

at 

acre-feet 

Evapora- 

flood 

over 

(Load  factor=0.75) 

in 
acre-ieet 

beginning 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

of 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-feet 

*Primary 

Second- 
ary 

Total 

1915 

Jan. 

895.000 

2,257,000 

239,000 

101,000 

0 

324,000 

0 

388 

97,400 

40,900 

138,300 

Feb. 

2,298,000 

2,488,000 

228,000 

242.000 

0 

1.625,000 

0 

386 

101,900 

108,100 

210,000 

Mar. 

1,264,000 

2,691,000 

250,000 

256,000 

0 

522,000 

0 

399 

104.200 

105.800 

210,000 

April 

l,lo;),000 

2,927,000 

249.000 

234,000 

7,000 

38,000 

618.000 

405 

109,000 

101,000 

210,000 

May 

1,2511,000 

2,940.000 

279,000 

220,000 

10,000 

0 

747,000 

406 

117,500 

92,.500 

210.000 

.Func 

572,000 

2.040,000 

283,000 

195,000 

12,000 

0 

99,000 

410 

124,200 

85.800 

210,000 

July 

343,000 

2,923,000 

298,000 

199,000 

14,000 

0 

0 

406 

12.5,400 

83.900 

209,300 

Aug. 

266,000 

2,755,000 

304,000 

100,000 

13,000 

0 

0 

400 

126,700 

41,709 

168,400 

Sept. 

215,000 

2,604,000 

282.000 

58,000 

10,000 

0 

0 

394 

120,000 

24.700 

144,700 

Oct. 

233,000 

2,469,000 

278,000 

46.000 

7,000 

0 

0 

388 

113,-400 

18,700 

132,100 

Nov. 

254,000 

2,371,000 

264,000 

78,000 

5,000 

0 

0 

384 

110,300 

32,400 

142,700 

Dec. 
Total  or 

699,000 

2,278,000 

270.000 

235.000 

0 

0 

0 

387 

109.400 

94,900 

201,300 

average 

9,454,000 

3,224.000 

1.964.000 

78,000 

2,509.000 

1,464.000 

396 

113.400 

69,000 

182.400 

1916 

Jan. 

1,160,000 

2,472,000 

240,000 

225,000 

0 

681,000 

0 

388 

97,400 

90,700 

188,100 

Feb. 

l.OHi.OOO 

2,492.000 

237.000 

252.000 

0 

1,077,000 

0 

384 

98,400 

107,900 

206,300 

iMar. 

1,215,000 

2,542.000 

252,000 

236,000 

0 

391,000 

0 

396 

104,200 

97,000 

201,200 

April 

678,000 

2,878,000 

249,000 

211.000 

7.000 

0 

149,000 

410 

109.000 

92,400 

201,400 

May 

485.000 

2.910.000 

276,000 

173,000 

10,000 

0 

26,000 

412 

117.500 

73,500 

191,000 

June 

353,000 

2,940,000 

283,000 

116,000 

12,000 

0 

0 

410 

124,200 

50.800 

175,000 

July 

316,000 

2,88ii  000 

298,000 

131,000 

14.000 

0 

0 

407 

125,400 

55.200 

180,600 

Aug. 

214,000 

2,755,000 

304,000 

78.000 

13,000 

0 

0 

400 

126,700 

32,.500 

159,200 

Sept. 

213,000 

2,604,000 

282,000 

56.000 

10,000 

0 

0 

394 

120,000 

23,800 

143,800 

Oct. 

236,000 

2,469,000 

278,000 

49.000 

7,000 

0 

0 

388 

113,400 

19,900 

133,300 

Nov. 

242,000 

2,371,000 

264,000 

66,000 

5,000 

0 

0 

384 

110,300 

27,500 

137,800 

Dec. 
Total  or 
average 

303,000 

2,278.000 

273.000 

111.000 

0 

0 

0 

380 

109,400 

44.500 

153,900 

7.127,000 

3.236.000 

1.704.000 

78.000 

2.149,000 

175.000 

396 

113,000 

59.500 

172.500 

1917 
Jan. 

312,000 

2,257,000 

242.000 

0 

0 

0 

0 

382 

97.400 

0 

97.400 

Feb. 

760,000 

2,327,000 

226,000 

26.000 

0 

178,000 

0 

387 

101,900 

11.600 

113,500 

Mar. 

459,000 

2,057,000 

247,000 

8.000 

0 

0 

0 

406 

104,200 

3,500 

107.700 

April 
May 

906,000 

2,861,000 

249,000 

196.000 

7.000 

0 

375,000 

408 

109.000 

85.600 

194.600 

580,000 

2,940,000 

276,000 

210,000 

10,000 

0 

84,000 

411 

117.500 

89,000 

206,500 

June 

32;',000 

2,940,000 

283,000 

92,000 

12.000 

0 

0 

410 

124.200 

40.300 

164,.500 

July 

238,000 

2,882,000 

297,000 

54.000 

14,000 

0 

0 

408 

125,400 

22,700 

148,100 

Aug. 

211,000 

2,755,000 

303,000 

49.000 

13,000 

0 

0 

402 

120,700 

20.400 

147.100 

Sept. 

185,000 

2,(101,000 

282,000 

28.000 

10.000 

0 

0 

394 

120,000 

11.900 

131.900 

Oct. 

200.000 

2,469,000 

278.000 

13.000 

7.000 

0 

0 

388 

113,400 

5.400 

118.800 

Nov. 

221,000 

2,371,000 

264.000 

48.000 

5.000 

0 

0 

384 

110.300 

20.000 

130,300 

Dec. 

298.000 

2.278,000 

273.000 

46.000 

0 

0 

0 

380 

109.400 

18.400 

127,800 

Total  or 
average 

4,705,000 

3.220,000 

770.000 

78.000 

178,000 

459.000 

397 

113,400 

27.400 

140,800 

1918 

Jan. 

249.000 

2,257.000 

243,000 

0 

0 

0 

0 

380 

97.400 

0 

97,400 

Feb. 

399,000 

2.263,000 

229,000 

0 

0 

0 

0 

383 

101.900 

0 

101,900 

Mar. 

772,00(J 

2,4.33.000 

251,000 

8.000 

0 

0 

6.000 

398 

104,200 

3,400 

107.600 

April 
May 

.556.000 

2,940,000 

247,000 

208,000 

7,000 

0 

94,000 

411 

109.000 

91,100 

200,100 

3II,(H)( 

2,940,000 

270,000 

28.000 

10,000 

0 

0 

412 

117.500 

12.000 

129.500 

Juno 

232,000 

2,910,000 

282,000 

0 

12,000 

0 

0 

412 

124,200 

0 

124,200 

July 

200,000 

2,878,000 

297,000 

12.000 

14,000 

0 

0 

408 

125.400 

5,100 

130.500 

Aug. 

192.000 

2,7.')5.OO0 

303,000 

27.000 

13.000 

0 

0 

402 

126.700 

11,200 

137.900 

Sept. 

186.00( 

2.604.000 

282.000 

29.000 

10.000 

0 

0 

394 

120.000 

12,400 

132,400 

Oct. 

258.000 

2,469.000 

278,000 

71.000 

7.000 

0 

0 

388 

113.400 

28.900 

142,300 

Nov. 

246.000 

2.371.000 

264.000 

70.000 

6.000 

0 

0 

384 

110.300 

29.000 

139.300 

Dec. 

258,000 

2.278,000 

270,000 

0.000 

0 

0 

0 

380 

109.400 

3.600 

113.000 

Total  or 
average 

3.862.000 

3,222.000 

462.000 

78.000 

0 

100.000 

396 

113.400 

16.300 

129.700 

•Total  primary  power  pro;l\iction  in  February  of  loap  yi^ars  taken  the  same  as  in  other  years. 


THE   CONTROL   OP   Fr,OOD«   BY   RESERVOIRS. 


277 


RESERVOIR  ON  SACRAMENTO  RIVER. 

MARILY  FOR  POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  4,  page  1 14.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.F.  =  0.80. 


Flood  control, 

holding  maximum  space  required  (454,000  ac 

-ff.)  In  reserve 

throughout  flood  season 

Maximum  controlled  flow  at  Red  Bluff  125,000  seo.-f t. 

Stage  of 

Power  draft 

Release 

Average  power 

yield 

Year  and 

reservoir 

through  turbines  in 

through 

Waste 

Average 

n  kilowatts 

month 

at 

acre-feet 

Evapora- 

flood 

over 

(Load  factor=0.75) 

beginning 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

of   , 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-feet 

*Primary 

Second- 
ary 

Total 

1915 

2,075,000 

234,000 

37,000 

0 

213,000 

0 

382 

94,100 

14,900 

109,000 

Jan. 

2.486,000 

223,000 

253,000 

0 

1,822,000 

0 

378 

98,500 

111,500 

210,000 

Feb. 

2,486,000 

250,000 

274,100 

0 

740,000 

0 

382 

100,500 

109,500 

210,000 

Mar. 

2.486,000 

245,000 

179,000 

7,000 

267,000 

7,000 

399 

105,300 

70,800 

182,100 

April 

2,940,000 

268,000 

231,000 

10,000 

0 

747,000 

408 

113,300 

96,700 

210,000 

May 

2,940,000 

274,000 

206,000 

12,000 

0 

80,000 

408 

119,700 

90,300 

210,000 

June 

2,940,000 

288,000 

211,000 

14,000 

0 

0 

406 

121,100 

88,900 

210,000 

July 

2,770,000 

295,000 

213,000 

13,000 

0 

0 

397 

122,300 

87,700 

210.000 

Aug. 

2,515,000 

276,000 

107,000 

9,000 

0 

0 

387 

115,800 

44,900 

160,700 

Sept. 

2,338,000 

272,000 

48,000 

7,000 

0 

0 

382 

109,500 

18,400 

127,900 

Oct. 

2,246,000 

259,000 

78,000 

4,000 

0 

0 

378 

106,500 

32,100 

138,600 

Nov. 

2,159,000 

263,000 

252,000 

0 

0 

0 

381 

105,600 

100,100 

205,700 

Dec. 

Tnfnl  nr 

3,117,000 

2,087,000 

76,000 

3,042,000 

834,000 

391 

109,400 

72,400 

181,800 

X Ulai  Ul 

average 

2,343,000 

232,000 

213,000 

0 

578,000 

0 

386 

94,100 

85,900 

180,000 

1916 

Jan. 

2,486,000 

226,000 

261,000 

0 

1,129,000 

0 

386 

95,100 

111,600 

206,700 

Feb. 

2,486,000 

249,000 

272,000 

0 

694,000 

0 

384 

100,500 

109,500 

210,000 

Mar. 

2,486,000 

246,000 

99,000 

7,000 

61,000 

0 

397 

105,300 

41,900 

147,200 

April 

2,751,000 

270,000 

175,000 

10,000 

0 

0 

404 

113,300 

73,400 

186,700 

May 

2,781,000 

276,000 

117,000 

11,000 

0 

0 

404 

119,700 

50,700 

170,400 

June 

2,730,000 

291,000 

131,000 

14,000 

0 

0 

400 

121,100 

54,600 

175,700 

July 

2,610,000 

298,000 

78,000 

12,000 

0 

0 

394 

122,300 

32,000 

154,300 

Aug. 

2,466,000 

270,000 

56,000 

9,000 

0 

0 

387 

115,800 

23,500 

139,300 

Sept. 

2,338,000 

272,000 

49,000 

7,000 

0 

0 

382 

109,500 

19,600 

129,100 

Oct. 

2,246,000 

259,000 

66,000 

4,000 

0 

0 

378 

106,500 

27,100 

133,600 

Nov. 

2,159,000 

269,000 

178,000 

0 

0 

0 

372 

105,600 

70,000 

175,600 

Dec. 

3,164,000 

1,695,000 

74,000 

2,462,000 

0 

389 

109,100 

58,300 

167,400 

average 

2,075,000 

239,000 

0 

0 

0 

0 

372 

94,100 

0 

94,100 

1917 

Jan. 

2,148,000 

223,000 

27,000 

0 

172,000 

0 

377 

98,500 

11,900 

110,400 

Feb. 

2,486,000 

245,000 

214,000 

0 

0 

0 

391 

100,500 

87,500 

188,000 

Mar. 

2,486,000 

245,000 

172,000 

7,000 

55,000 

0 

399 

105,300 

73,500 

178,800 

April 

2,913,000 

267,000 

226,000 

10,000 

0 

57,000 

410 

113,300 

96,700 

210,000 

May 

2,933,000 

274,000 

209,000 

12,000 

0 

0 

407 

119,700 

90,300 

210,000 

June 

2,767,000 

231,000 

90,000 

14,000 

0 

0 

400 

121,100 

37,.500 

158,600 

July 

2,610,000 

298,000 

48,000 

12,000 

0 

0 

394 

122,300 

19.800 

142,100 

Aug. 

2,466,000 

276,000 

28,000 

9,000 

0 

0 

388 

115,800 

11,700 

127,500 

Sept. 

2,338,000 

272,000 

13,000 

7,000 

0 

0 

382 

109,500 

5,200 

114,700 

Oct. 

2,246,000 

259,000 

48,000 

4,000 

0 

0 

378 

106,500 

19,700 

126,200 

Nov. 

2.159,000 

269,000 

113,000 

0 

0 

0 

372 

105,600 

44,400 

150,000 

Dec. 
Total  or 
average 

3,158,000 

1,188,000 

75,000 

227,000 

57,000 

389 

109,400 

41,700 

151,100 

2,075,000 

240,000 

0 

0 

0 

0 

370 

94,100 

0 

94,100 

1918 

Jan. 

2,084,000 

224,000 

0 

0 

0 

0 

376 

98,500 

0 

98,500 

Feb. 

2.259,000 

249.000 

105,000 

0 

191,000 

0 

385 

100,500 

42,500 

143,000 

Mar. 

2,486,000 

246,000 

58,000 

7,000 

20,000 

0 

397 

105,300 

24,400 

129,700 

April 

2,711,000 

270,000 

0 

10,000 

0 

0 

404 

113,300 

0 

113,300 

May 

2,745,000 

276,000 

0 

11,000 

0 

0 

403 

119,700 

•    0 

119,700 

June 

2,690,000 

291,000 

0 

14,000 

0 

0 

400 

121,100 

0 

121,100 

July 

2,585,000 

296,000 

3,000 

12,000 

0 

0 

394 

122,300 

1,200 

123,500 

Aug. 

2,466,000 

276,000 

29,000 

9,000 

0 

0 

388 

115,800 

12,200 

128,000 

Sept. 

2,338,000 

272,000 

71,000 

7,000 

0 

0 

382 

109,500 

28,500 

138,000 

Oct. 

2,246,000 

259,000 

70,000 

4,000 

0 

0 

378 

106,500 

28,800 

135.300 

Nov. 

2,159,000 

269,900 

73,000 

0 

0 

0 

372 

105,600 

28,800 

134,400 

Dec. 
Total  or 
average 

3,168,000 

409,000 

74,000 

211,000 

0 

387 

109,400 

14.000 

123.400 

278 


WATER  RESOURCES  OP   CALIFORNIA. 


TABLE  4a  ^Continued).     KENNETT 

COMPARISON  OF  WATER  AND  POWER  YIELD,  OPERATING  PRI 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

fFor  corresfX)nding  yearly  sum 
Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Flood  control  by  reservoir  operatin 

g  diagram 

Maxinum  controlled  flow  at  Red  Bluff  12.5.000  sec.-ft. 

Esti- 
mated 
run-off 

Maximum  reservoir  space  required  454,000  ac. 

ft. 

Year  and 

at 

Stage  of 

Power  draft 

Release 

Average  power  yield 

month 

dam 

reservoir 

tlirough  turbines  in 

through 

Waste 

Average 

n  kilowatts 

site 

at 

acre-feet 

Evapora- 

flood 

over 

(Load  factor=0.75) 

in 
acre-feet 

beginning 
of 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-feet 

•Primarj 

Second- 
ary 

Total 

1919 

Jan. 

-.587.000 

2.257,000 

240,00C 

71,000 

1               0 

34,000 

0 

385 

97.400 

29,000 

126,400 

Fcl). 

1,163.000 

2.499,000 

226,000 

222,000 

0 

•     671,000 

0 

387 

101.900 

99,600|    201,500 

Mir. 

959.000 

2,543,000 

251,000 

230,000 

0 

196.000 

0 

397 

104,200 

9.5,200;    199,400 

April 

7.i2.000 

2.825,000 

249,000 

22*,000 

7.000 

18,000 

139.000 

409 

109,000 

97.600 

206,600 

M  ly 

438.000 

2,940,000 

277,000 

151,000 

10,000 

0 

0 

410 

117,500 

64,100 

181,600 

.Ii;iie 

2.52.000 

2,940,000 

282,000 

16.000 

12,000 

0 

0 

412 

124,200 

7,100 

131.300 

July 

219.000 

2,882,000 

297,000 

35,000 

11.000 

0 

0 

408 

125,400 

14,800 

140,200 

Au<. 

199.000 

2,755,000 

303,000 

!       34,000 

13,000 

0 

0 

402 

126,700 

14,200 

140.900 

Sept. 

168,000 

2,604,0001     282,000 

;        11,000 

10,000 

0 

0 

394 

120.000 

4,600 

124,600 

Oct. 

203.000 

2,469,000 

278,000 

i        16,000 

7.000 

0 

0 

388 

113,400 

6,500 

119.900 

Nov. 

186,000 

2,371,000 

264,000 

1        10.000 

5,000 

0 

0 

384 

110,300 

4,200 

114.500 

Dec. 

180,000 

2,278,000 

274,000 

0 

0 

0 

0 

378 

109,400 

0 

109,400 

Totil  or 

average 

5,306,000 

3.223.000 

1.020,000 

78,000 

919,000 

139.000 

396 

113,400 

36,000 

149.400 

1920 

Jan. 

207,000 

2.184,000 

245,000 

0 

0 

0 

0 

375 

97,400 

0 

97.400 

Feb. 

176,000 

2,146,0001     233,000 

1                0 

0 

0 

0 

372 

98,400 

0 

98,400 

Mar. 

372,000 

2.080. nnn     on?  oon 

0 

0 

0 

0 

374 

104.200 

0 

104,200 

April 

493,000 

2,'l98'iH'i      J',  J 

0 

6.000 

0 

0 

383 

109,000 

0 

109,000 

-May 

286,000 

2.423  n"i        _-"-> 

0 

9.000 

0 

0 

388 

117,500 

0 

117..500 

June 

216,000  •:  •,-: 

0 

10.000 

0 

0 

386 

124,200 

0 

124.200 

July 

192,0011 

0 

12.000 

0 

0 

380 

125.400 

0 

125,400 

Aug. 

176,000    . 

0 

11,000 

0 

0 

372 

126.700 

0 

126,700 

Sept. 

140.000 

0 

8,000 

0 

0 

363 

120,000 

0 

120,000 

Oct. 

180,0011 

0 

6,000 

0 

0 

354 

113.400 

0 

113,400 

Nov. 

896,001  i 

25,000 

4,000 

0 

0 

359 

110,300 

10,400,    120,700 

Dec. 
Total  or 

1,121,000 

^,oi:',V\Ji)        .iOD.UUO 

245.000 

0 

202,000 

0 

395 

109,400 

100,600 

210,000 

average 

4,455,000 

3,374,000 

270,000 

66,000 

202,000 

0 

375 

113,000 

9,400 

122,400 

1921 

Jan. 

1,492,000 

2,727,000 

239,000 

277,000 

0 

1.050,000 

0 

390 

97.400 

112.600 

210.000 

Feb. 

1,035,000 

2.653,000 

226,000 

240,000 

0 

660,000 

0 

390 

101.900 

108,100 

210,000 

Mar. 

982,000 

2.562,000 

252,000 

244,000 

0 

226,000 

0 

396 

104,200 

100.900 

205.100 

April 
May 

559,000 

2,822,000 

246,000 

164,000 

7,000 

0 

24,000 

411 

109,000 

71,900 

180.900 

493,000 

2,940,000 

276,000 

195,000 

10,000 

0 

12,000 

411 

117,500 

83,200 

200,700 

June 

316,000 

2,940,000 

283,000 

79,000 

12,000 

0 

0 

410 

124,200 

34,600 

158,800 

July 

220,000 

2,882,000 

297,000 

36,000 

14,000 

0 

0 

408 

125,400 

15,200 

140,600 

Aug. 

192,000 

2,755,000 

303,000 

27.000 

13.000 

0 

0 

402 

126,700 

11,200 

137,900 

Sept. 

175,000 

2,604,000 

282,000 

18,000 

10,000 

0 

0 

394 

120.000 

7,800 

127,800 

Oct. 

196,000 

2,469,000 

277,000 

0 

7.000 

0 

0 

389 

113,400 

0 

113,400 

Nov. 

205.000 

2.381,000 

264,000 

39,000 

5,000 

0 

0 

384 

110.300 

16,300 

126,600 

Dec. 
Total  or 

390,000 

2,278,000 

273,000 

72,000 

0 

0 

0 

381 

109.400 

28,900 

138,300 

average 

6,255,000 

3,218,000 

1,391,000 

78,000 

1.936.000 

36,000 

397 

113,400 

48,900 

162,300 

1922 

Jan. 

300,000 

2,323,000 

240,000 

0 

0 

0 

0 

387 

97,400 

0| 

97,400 

Feb. 

679,000 

2,383,000 

225,000 

44,000 

0 

136,000 

o' 

392    i 

101,900 

19,900     121,800 

Mar. 

567,000 

2,657,000      246.000 

17,000 

0 

0 

21,000 

407 

104,200 

7,300l    111,500 

April 
May 

604,000 

2.940.000      248,090 

214,000 

7,000 

0 

135,000 

410 

109,000 

93,600,    202,600 

577,000 

?.940,000      276.000 

209,000 

10,000 

0 

82,000 

411 

117,500 

88,300;    205.800 

June 

317,000 

2,940,000      283,000 

80,000 

12,000 

0 

0 

410    1 

124,200 

35.000     159,200 

July 

203,000 

2,882.000      297,000 

19,000 

14,000 

0 

0 

408 

125.400 

7,900 

133,300 

Aug. 

182,000 

2,755,000      303,000 

17,000 

13.000 

0 

0 

402 

126,700 

7,100 

133,800 

Sept. 

161,000 

2,604,000;     282.000 

4,000 

10,000 

0 

0 
0 

394 

120,000 

1,700 

121,700 

Oct. 

208.000 

2.469,000      278,000 

21,000 

7,000 

0 

388 

113,400 

8,600 

122,000 

Nov. 

244,000 

2,371.000      264,000 

68.000 

5,000 

0 

0 

384 

110,300 

28,300 

138,600 

Dec. 
Total  or 

462,000 

2,278,000     273.000 

139.000 

0 

0 

0 

380 

109,400 

55,100j    164,500 

avenge 

4.604,000 

3,215,000 

832,000 

78,000' 

1 

136,000| 

238.000' 

898 

113,400 

29,400 

142,800 

_^Tot^_Erimary  power  production  in  February  of  leap  years  taken  the  game  aa  in  other  years. 


THE    CONTROL   OF    FLOODS   HY    RERERVOIRR. 


279 


RESERVOIR  ON  SACRAMENTO  RIVER. 

MARILY  FOR  POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  4,  page  114.) 

Installed  capacity  of  power  plant  400,000  k.v  a.     P.F.  =  0.80. 


Flood  control, 

holding  maximum  space  requirea  (454,000  ac 

-ft.)  in  reserve 

throughout  flood  season 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Stage  of 

Power  draft 

Release 

Average  power  yield 

reservoir 

through  turbines  in 

through 

Waste 

Average 

m  kilowatt 

Year  and 

at 

acre 

-feet 

Evapora- 

flood 

over 

(Load  factor=0.75) 

month 

beginning 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

leet 

of 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-ieet 

*Primary 

Second- 
ary 

Total 

2,075,000 

236,000 

0 

0 

0 

0 

377 

94,100 

0 

94,100 

1919 

Jan. 

2,426,000 

220,000 

188,000 

0 

695,000 

0 

386 

98,500 

83,800 

182,300 

Feb. 

2,486,000 

248,000 

270,000 

0 

441,000 

0 

386 

100,500 

103,500 

210,000 

Mar. 

2,486,000 

246,000 

109,000 

7,000 

109,000 

0 

396 

105,300 

46,400 

151,700 

April 

2,767,000 

270,000 

144,000 

10,000 

0 

0 

405 

113,300 

60,500 

173,800 

May 

2,781.000 

275,000 

17.000 

11,000 

0 

0 

405 

119,700 

7,400 

127,100 

June 

2,730,000 

290,000 

35,000 

14,000 

0 

0 

401 

121,100 

14,700 

135,800 

July 

2,610.000 

296,000 

35,000 

12,000 

0 

0 

394 

122.300 

14,400 

136.700 

Aug. 

2,466,000 

276,000 

11,000 

9,000 

0 

0 

388 

115,800 

4,600 

120,400 

Sept. 

2,338,000 

272,000 

16,000 

7,000 

0 

0 

382 

109,500 

6,500 

116,000 

Oct. 

2,246,000 

259,000 

10,000 

4,000 

0 

0 

378 

106,500 

4,200 

110,700 

Nov. 

2,159,000 

268,000 

0 

0 

0 

0 

372 

105,600 

0 

105,600 

Dec. 
Total  or 
average 

3,156,000 

835,000 

74,000 

1,245,000 

0 

389 

109,400 

29,000 

138,400 

2,071,000 

239,000 

0 

0 

0 

0 

370 

94,100 

0 

94,100 

1920 

Jan. 

2,039,000 

236,000 

0 

0 

0 

0 

367 

95,100 

0 

95,100 

Feb. 

1,979,000 

257.000 

0 

0 

0 

0 

368 

100,500 

0 

100,500 

Mar. 

2,094,000 

256,000 

0 

6,000 

0 

0 

377 

105,300 

0 

105,300 

April 

2,325,000 

281,000 

0 

9,000 

0 

0 

384 

113,300 

0 

113,300 

May 

2,321,000 

288,000 

0 

10,000 

0 

0 

382 

119,700 

0 

119,700 

June 

2,239,000 

306,000 

0 

12,000 

0 

0 

376 

121,100 

0 

121,100 

July 

2,113,000 

314.000 

0 

11,000 

0 

0 

368 

122,300 

0 

122.300 

Aug. 

1,964,000 

293,000 

0 

8,000 

0 

0 

360 

115,800 

0 

115,800 

Sept. 

1,803,000 

293,000 

0 

6.000 

0 

0 

351 

109,500 

0 

109,500 

Oct. 

1,684,000 

266,000 

0 

4,000 

0 

0 

365 

106.500 

0 

106,500 

Nov. 

2,310,000 

261,000 

192,000 

0 

492,000 

0 

386 

105,600 

77,300 

182,900 

Dec. 
Total  or 
average 

3,290,000 

192,000 

66,000 

492,000 

0 

371 

109,100 

6,500 

115,600 

2,486,000 

233,000 

288,000 

0 

971,000 

0 

385 

94,100 

115,900 

210,000 

1921 

Jan. 

2,486,000 

220,000 

250,000 

0 

565,000 

0 

385 

98,500 

111,500 

210,000 

Feb. 

2,486,000 

248,000 

270,000 

0 

464,000 

0 

386 

100,500 

109,500 

210,000 

Mar. 

2,486,000 

246,000 

59,000 

7,000 

43,000 

0 

395 

105,300 

24,400 

129,700 

April 

2,690,000 

270,000 

122,000 

10,000 

0 

0 

404 

113,300 

51,100 

164,400 

May 

2,781,000 

276,000 

80,000 

11,000 

0 

0 

404 

119,700 

34,700 

154,400 

June 

2,730,000 

290,000 

38,000 

14,000 

0 

0 

400 

121,100 

15,100 

130,200 

July 

2,610,000 

296,000 

28,000 

12,000 

0 

0 

394 

122,300 

11,600 

133,900 

Aug. 

2,466,000 

276,000 

18,000 

9,000 

0 

0 

388 

115,800 

7,500 

123,300 

Sept. 

2.338,000 

272,000 

9,000 

7,000 

0 

0 

382 

109,500 

3,600 

113,100 

Oct. 

2,246,000 

259,000 

29,000 

4,000 

0 

0 

378 

106,500 

11,900 

118,400 

Nov. 

2,159,000 

268,000 

120,000 

0 

0 

0 

373 

105,600 

47,200 

152,800 

Dec. 
Totil  or 
average 

3,154,000 

1,309,000 

74,000 

2,043,000 

0 

390 

109,400 

45,100 

154,500 

2,161,000 

237,000 

0 

0 

0 

0 

376 

94,100 

0 

94,100 

1922 

Jan. 

2,224,000 

221,000 

62,000 

0 

134,000 

0 

383 

98,500 

28,000 

126,500 

Feb. 

2,486,000 

246,000 

239,000 

0 

82,000 

0 

390 

100,500 

97,300 

197,800 

Mar. 

2,486,000 

247,000 

59,000 

7,000 

80,000 

0 

395 

105,300 

24,400 

129,700 

April 

2,697,000 

270,000 

178,000 

10,000 

0 

0 

405 

113,300 

74,900 

188,200 

May 

2,816,000 

276,000 

116,000 

11,000 

0 

0 

404 

119,700 

50,300 

170,000 

June 

2,730,000 

290,000 

19.000 

14,000 

0 

0 

400 

121,100 

7,900 

129,000 

July 

2,610,000 

296,000 

18,000 

12,000 

0 

0 

394 

122,300 

7,400- 

129,700 

Aug. 

2,466.000 

276,000 

4,000 

9,000 

0 

0 

388 

115,800 

1,700 

117,500 

Sept. 

2,338,000 

272,000 

21,000 

7,000 

0 

0 

382 

109,500 

8,500 

118,000 

Oct. 

2,246,000 

259,000 

68,000 

4,000 

0 

0 

378 

106,500 

27,900 

134,400 

Nov. 

2,159,000 

269,000 

197,000 

0 

0 

0 

372 

105,600 

76,900 

182,500 

Dec. 
Total  or 
average 

3,159,000 

981,000 

74,000 

296,000 

0 

389 

109,400 

33,900 

143,300 

280 


WATER  RESOURCES  OP   fALIFORXIA. 


TABLE  4a  (Concluded).     KENNETT 

COMPARISON  OF  WATER  AND  POWER  YIELD,  OPERATING  PRI 

FOR 

TWO  METHODS  OF 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Height  of  dam  420  feet.     Capacity  of  reservoir  2,940,000  acre-feet. 


Flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-ft. 

Esti- 

Maximum reservoir  space 

required  454,000  ac. 

-ft. 

mated 
run-off 

Year  and 

at 

Stage  of 

Power  draft 

Release 

Average  power  yield 

month 

dam 

reservoir 

through  turbines  in 

through 

Waste 

Average 

in  kilowatts 

site 

at 

acre-feet 

Evapora- 

flood 

over 

(Load  factor=^0.75) 

in 
acre-feet 

beginning 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

of  _ 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-feet 

*Primary 

Second- 
ary 

Total 

1923 

Jan. 

467,000 

2,328,000 

240,000 

130,000 

0 

0 

0 

385 

97,400 

52,400    149,800 

Feb. 

297,000 

2,425,000 

225,000 

0 

0 

0 

0 

390 

101,900 

0    101,900 

Mar. 

287,000 

2,497,000 

253,000 

0 

0 

0 

0 

393 

104,200 

0     104,200 

.\i)ril 

632,000 

2,531,000 

250,000 

0 

7,000 

0 

0 

405 

109,000 

0!    109,000 

May 

322,000 

2,906,000 

275,000 

3,000 

10,000 

0 

0 

412 

117,500 

1.300 

118,800 

.June 

236.000 

2,940,000 

282,000 

0 

12,000 

0 

•  0 

412 

124,200 

0 

124,200 

July 

184,000 

2,882,000 

297,000 

0 

14,000 

0 

0 

408 

125,400 

0 

125,400 

Aug. 

10.5.000 

2,755,000 

303,000 

0 

13,000 

0 

0 

402 

126,700 

0 

126.700 

.Sept. 

157,000 

2,604,000 

282,000 

0 

10,000 

0 

0 

394 

120,000 

0 

120,000 

Oct. 

187,000 

2,469,000 

278,000 

0 

7,000 

0 

0 

388 

113,400 

0 

113,400 

Nov. 

176.000 

2,371,000 

264,000 

0 

5.000 

0 

0 

384 

110,300 

0 

110.300 

Dec. 
Total  or 

184,000 

2,278,000 

274,000 

0 

0 

0 

0 

379 

109,400 

O;    109.400 

average 

3,294.000 

3,223,000 

133,000 

78,000 

0 

0 

398 

113,400 

4.600 

118,000 

1924 
Jan. 

203,000 

2,188,000 

245.000 

0 

0 

0 

0 

376 

97,400 

0 

97,400 

Feb. 

332,000 

2,146,000 

231,000 

0 

0 

0 

0 

378 

98.400 

0 

98,400 

Mar. 

200,000 

2,247,000 

260,000 

0 

0 

0 

0 

379 

104,200 

0 

104.200 

April 
May 

176,000!  2,187,000 

266,000 

0 

6,000 

0 

0 

374 

109,000 

0 

109,000 

1.5.5,000!  2,091,000      301,000 

0 

8,000 

0 

0 

367 

117.500 

0 

117,500 

June 

141.000   1,937,000      315,000 

0 

9,000 

0 

0 

358 

124,200 

0    124,200 

July 

140,000   1,754,000      341,000 

0 

10,000 

0 

0 

345 

125,400 

0     125,400 

Aug. 

140,000i  1,543,000 

360,000 

0 

8,000 

0 

0 

330 

126,700 

0     126,700 

Sept. 

128,000  1,315,000 

349,000 

0 

6,000 

0 

0 

312 

120,000 

0     120,000 

Oct. 

178,000;  1,088.000 

363,000 

0 

4.000 

0 

0 

293 

113,400 

0     113,400 

Nov. 

317,000 

899,000 

356,000 

0 

2,000 

0 

0 

282 

110,300 

0     110,300 

Dec. 
Total  or 
average 

321,000 

858,000 

372,000 

» 

0 

0 

0 

277 

109,400 

Q^    109,400 

2,431,000 

3,759.000 

0 

53,000 

0 

0 

339 

113,000 

O'    113,000 

1925 
Jan. 

301,000 

807,000 

336,000 

0 

0 

0 

0 

273 

97,400 

0      97.400 

Feb. 

1,769,000 

772,000 

264,000 

0 

0 

0 

0 

326 

101,900 

0    101.900 

Mar. 

563,000 

2,277,000 

255.000 

0 

0 

0 

0 

389 

104,200 

0     101,200 

April 
May 

926.000 

2,585,000 

250,000 

124,000 

7,000 

0 

190,000 

403 

109,000 

53,800     162,800 

474,000 

2,940,000 

276,000 

167.000 

10,000 

21.000 

412 

117,500 

70,800     188,300 

June 

276.000 

2,940,000 

282,000 

40.000 

12,000 

0 

0 

411 

124,200 

17,500t    141,700 

July 

173,000 

2,882.000 

297,000 

0 

14.000 

0 

0 

408 

125.400 

Ol    125,400 

Aug. 

167,000 

2,744.000 

304,000 

0 

13.000 

0 

0 

400 

126.700 

0     126.700 

Sept. 

163,000 

2,594.000 

282.000 

0 

10.000 

0 

0 

394 

120.000 

0     120,000 

Oct. 

181,000 

2,465,000 

278.000 

0 

7.000 

0 

0 

388 

113,400 

0,    113,400 

Nov. 

192,000 

2,361,000 

264,000 

6.000 

5,000 

0 

0 

384 

110,300 

2,500     112,800 

Dec. 
Total  or 
average 

235,000 

2,278,000 

273.000 

0 

0 

0 

0 

380 

109,400 

OJ    109,400 

5,420,000 

3,361.000 

337,000 

78.000 

0 

211.000 

381 

113,400 

12,100i    125,.500 

Total  for 

30-year 
period, 

189ft.1928 

188^012,000 

97,481,000 

37,094,000 

2.300,000 

40,414,000 

10.739,000 

Average 
for 

30-year 

period, 

1896-1926 

6.267,000 

3,249,000 

1,236,000 

77,000 

1,347,000 

358,000 

393.8 

113,400 

43,400 

156.800 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


281 


RESERVOIR  ON  SACRAMENTO  RIVER. 

MARILY  FOR  POWER  GENERATION  WITH  INCIDENTAL  IRRIGATION 


FLOOD  CONTROL. 

tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  4,  page  1 14.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.F.  =  0.80. 


Flood  control, 

liolding  maximum  space  required  (454,000  ac. 

-ft.)  in  reserve 

throughout  flood  season 

Maximum  controlled  flow  at  Red  Bluff  125,000  sec.-it. 

Stage  of 

Power  draft 

Release 

Average  power 

vieKl 

reservoir 

through  turbines  in 

through 

Waste 

Average 

in  kilowatts 

Yeir  and 

at 

acre-feet 

Evapora- 

flood 

over 

(Load  faetor= 

3.75) 

month 

beginning 

tion  in 
acre-feet 

control 
outlets 

spillway 
in 

power 

head  in 

feet 

of 

month  in 
acre-feet 

Primary 

Second- 
ary 

in 
acre-feet 

acre-feet 

*Primary 

Second- 
ary 

Total 

1923 

2,155.000 

235,000 

0 

0 

0 

0 

380 

94,100 

0 

94,100 

Jan. 

2,387,000 

218,000 

0 

0 

0 

0 

390 

98,500 

0 

98,500 

Feb. 

2,466,000 

245,000 

22,000 

0 

0 

0 

392 

100,500 

9,000 

109,500 

Mar. 

2,486,000 

246,000 

49,000 

7,000 

77,000 

0 

398 

105,300 

20,600 

125,900 

April 

2,739,000 

270,000 

0 

10,000 

0 

0 

406 

113,300 

0 

■  113,300 

May 

2,781,000 

276,000 

0 

11,000 

0 

0 

405 

119,700 

0 

119,700 

.June 

2,730,000 

290,000 

0 

14,000 

0 

0 

401 

121,100 

0 

121,100 

July 

2,610,000 

297,000 

0 

12,000 

0 

0 

394 

122,300 

0 

122,300 

Aug. 

2,466,000 

270,000 

0 

9,000 

0 

0 

388 

115,800 

0 

115,800 

Sept. 

2,338,000 

272,000 

0 

7,000 

0 

0 

■      382 

109,500 

0 

109,500 

Oct. 

2,246,000 

259,000 

0 

4,000 

0 

0 

378 

106,500 

0 

106,500 

Nov. 

2,159,000 

268.000 

0 

0 

0 

0 

372 

105,600 

0 

105,600 

Dec. 

Total  or 
average 

3,152,000 

71,000 

74,000 

77,000 

0 

390 

109,400 

2,500 

111,900 

1924 

2,075,000 

240,000 

0 

0 

0 

0 

370 

94,100 

0 

94,100 

Jan. 

2,038,000 

226.000 

0 

0 

0 

0 

372 

95,100 

0 

95,100 

Feb. 

2,144,000 

255,000 

0 

0 

0 

0 

374 

100,500 

0 

100,500 

Mar. 

2,089,000 

261,000 

0 

6,000 

0 

0 

369 

105,300 

0 

105,300 

April 

1,998,000 

295,000 

0 

8,000 

0 

0 

362 

113,300 

0 

113,300 

May 

1,850,000 

309,000 

0 

9,000 

0 

0 

352 

119,700 

0 

119,700 

June 

1,673,000 

334,000 

0 

10,000 

0 

0 

340 

121,100 

0 

121,100 

July 

1,469,000 

354,000 

0 

8,000 

0 

0 

324 

122,300 

0 

122,300 

Aug. 

1,247,000 

343,000 

0 

6,000 

0 

0 

306 

115,800 

0 

115,800 

Sept. 

1,026,000 

357,000 

0 

4,000 

0 

0 

288 

109,500 

0 

109,500 

Oct. 

843,000 

351,000 

0 

2,000 

0 

0 

276 

106,500 

0 

106,500 

Nov. 

807,000 

367,000 

0 

0 

0 

0 

272 

105,600 

0 

105,600 

Dec. 
Total  or 
average 

3,692,000 

0 

53,000 

0 

0 

334 

109,100 

0 

109,100 

1925 

761,000 

332,000 

0 

0 

0 

0 

268 

94,100 

0 

94,100 

Jan. 

730,000 

258,000 

0 

0 

0 

0 

323 

98,500 

0 

98,500 

Feb. 

2,241,000 

247,000 

54,000 

0 

17,000 

0 

388 

100,.500 

21,900 

122,400 

Mar. 

2,486,000 

245,000 

155,000 

7,000 

130,000 

0 

399 

105,300 

66,500 

171,800 

April 

2,875,000 

268,000 

231,000 

10,000 

0 

0 

408 

113,300 

96,700 

210,000 

May 

2,840,000 

275,000 

99,000 

12.000 

0 

0 

405 

119,700 

42,900 

162,600 

June 

2,730,000 

291,000 

0 

14,000 

0 

0 

400 

121,100 

0 

121,100 

July 

2,598,000 

298,000 

0 

12,000 

0 

0 

394 

122,300 

0 

122,300 

Aug. 

2.455,000 

276,000 

0 

9,000 

0 

0 

387 

115,800 

0 

115,800 

Sept. 

2.333,000 

272,000 

0 

7,000 

0 

0 

382 

109,.500 

0 

109,500 

Oct. 

2,235.000 

259,000 

5,000 

4,000 

0 

0 

377 

106,500 

2,100 

108,600 

Nov. 

2,159,000 

269,000 

50,000 

0 

0 

0 

372 

105,600 

19,600 

125,200 

Dec. 
Total  or 
average 

3,290,000 

594,000 

75,000 

147,000 

0 

375 

109,400 

20,900 

130.300 

Total  for 

30-year 
period, 
1896-1926 

95.438,000 

40,980,000 

2,208,000 

45,734,000 

3,652,000 

Average 
for 

30-year 
period, 
1896-1926 

3,181.000 

1,368,000 

74,000 

1,524,000 

122,000 

386.9 

109,400 

47,300 

156,700 

18—52411 


282 


WATER  RESOURCES  OF    CALIFORNIA. 


Height  of  dam  420  feet. 


TABLE  5a.     KENNETT  RESER 

SUMMARY  OF  POWER  YIELD  BY  MONTHS 

Summary  of  Tables 

(For  corresponding  yearly  sum 
Capacity  of  reservoir  2,940,000  acre-feet. 


Operating  primarily  for  power  generation  with  incid 

jntal  irrigation 

Average  power  yield 

in  kilowatts 

(Load  facto 

r=0.75) 

Coordinated  with  flood  control 

With  flood  control,  holding 

Year  and 

by  reservoir  operating  diagram 

maximum  reservoirspace 

month 

Will 

Maximum  controlled  flow 

require 

i  (454,000  ac 

.-ft.)  in 

out  nooil  comroi             i 

at  Red  Bluff  125,00( 

sec.-ft. 

resen-e  throughout  flood  season 

Maximum  reservoir  space 

Maximum  controlled  flow 

required  454,000  aore-feet 

at  Red  Bluff  125.00C 

sec.-ft. 

•Primary 

Secondary 

Total 

•Primary 

Secondary 

Total 

•Primary 

Secondary 

Total 

1896 

Jan. 

97,400 

40,500 

137,900 

97,400 

47,200 

144.600 

94.100 

52,300 

146.400 

Feb. 

08,400 

78,000 

176,400 

98,400 

22,300 

120,700 

95,100 

79.300 

174,400 

Mar. 

104.200 

91,100 

195,300 

104,200 

20,400 

124,600 

100,500 

91.400 

191,900 

April 

109,000 

101,000 

210,000 

109,000 

101,000 

210,000 

10o,300 

49.000 

154,300 

May 

117,500 

92,500 

210,000 

117,500 

92,500 

210,000 

113,300 

96,700 

210,000 

Jun" 

124,200 

85,800 

210,000 

124,200 

85,800 

210,000 

119,700 

90,300 

210,000 

July 

125,400 

63,700 

189,100 

125,400 

03,700 

189,100 

121.100 

88,900 

210,000 

Aug. 

126,700 

42,500 

169,200 

126,700 

42,500 

169.200 

122,300 

81,600 

203,900 

Sept. 

120,000 

42,800 

162,800 

120,000 

42,800 

162.800 

llo,800 

41,800 

157,600 

Oct. 

113,400 

30,500 

143,900 

113,400 

30,500 

143,900 

109,500 

30,100 

139.600 

Nov. 

110,300 

66,800 

177,100 

If  0,300 

66,800 

177,100 

106,.500 

69,700 

176,200 

Dec 

109,400 

100,600 

210,000 

109,400 

100,600 

210,000 

105,600 

104,400 

210,000 

Total  or 
average 

113,000 

09,500 

182,500 

113,000 

59,700 

172,700 

109,100 

73,000 

182,100 

1897 

Jan. 

97,400 

55,000 

1.52,400 

97,400 

71,000 

168,400 

94,100 

83,300 

177,400 

Feb. 

101,900 

108,100 

210,000 

101.900 

108,100 

210,000 

98,500 

111,500 

210,000 

Mar. 

104,200 

105,800 

210,000 

104,200 

53,200 

157,400 

100,500 

107,000 

207,500 

April 

109,000 

101,000 

210,000 

109,000 

81,400 

190,400 

105,300 

66,500 

171,800 

May 

117,500 

82,500 

200,000 

117,500 

82,500 

200,000 

113,300 

96,700 

210,000 

June 

124,200 

32,100 

156,300 

124,200 

32,100 

156,300 

119,700 

90,300 

210,000 

July 

125,400 

37,900 

163,300 

125,400 

37,000 

163,300 

121,100 

37,600 

158,700 

Aug. 

126,700 

36.200 

162,900 

126,700 

36,200 

162,900 

122,300 

30,200 

1.58,500 

Sept. 

120,000 

3>',200 

158,200 

120,000 

38,200 

158,200 

115.800 

37,200 

153,000 

Oct. 

113,400 

30,500 

143,900 

113,400 

30,500 

143,900 

109,-500 

30,100 

139,600 

Nov. 

110,300 

40,300 

150,600 

110,300 

40,300 

150,600 

106,500 

40,300 

140,800 

Dec. 
Total  or 
average 

109,400 

45,200 

154,600 

109,400 

45,200 

154,600 

105,600 

71,500 

177,100 

113,400 

59,100 

172,500 

113,400 

54,300 

167,700 

109,400 

67.100 

176,500 

1898 

Jan. 

97,400 

0 

97,400 

97,400 

0 

97,400 

94,100 

0 

94,100 

Feb. 

101,900 

0 

101,900 

101,900 

0 

101,900 

98,500 

0 

98,500 

Mar. 

104,200 

0 

104,200 

104,200 

0 

104,200 

100,500 

0 

100,500 

April 
May 

109,000 

0 

109,000 

109,000 

0 

109,000 

105,300 

0 

105,300 

117,500 

0 

117,500 

117,500 

0 

117.500 

113,300 

0 

113,300 

June 

124,200 

0 

124,200 

124,200 

0 

124,200 

119,700 

0 

119,700 

July 

125.400 

0 

125,400 

125,400 

0 

125,400 

121,100 

0 

121,100 

AUR. 

120,700 

0 

126,700 

126.700 

0 

126,700 

122,300 

0 

122,300 

Sept. 

120,000 

0 

120,000 

120,000 

0 

120,000 

115,800 

0 

115,800 

Oct. 

113,400 

0 

113,400 

113,400 

0 

113,400 

109,500 

0 

109,500 

Nov. 

110.300 

8,800 

119,100 

110,300 

8,800 

119,100 

106,500 

5.300 

111,800 

Dec. 
Total  or 
avoraKc 

109.400 

0 

109,400 

109,400 

0 

109.400 

105,600 

13.000 

118,600 

113,400 

700 

114,100 

113.400 

700 

114.100 

109,400 

1.500 

110,900 

1899 

Jan. 

97,400 

0 

97,400 

97,400 

18,400 

115.800 

94,100 

0 

94,100 

Feb. 

101,900 

0 

101,900 

101,900 

0 

101,900 

98,500 

0 

98,500 

Mar. 

10t,200 

27.300 

131,500 

104,200 

23,900 

128,100 

100,500 

85.900 

186,400 

April 
May 

109.000 

76.300 

185,300 

109,000 

61,500 

170,500 

105,300 

24,400 

129.700 

117,500 

18.800 

136,300 

117,500 

18,800 

136,300 

113,300 

0 

113,300 

June 

124.200 

25,700 

149,900 

124,200 

25,700 

149,900 

119,700 

0 

119,700 

July 

125,400 

23,100 

148,500 

125,400 

23,100 

148,500 

121,100 

0 

121,100 

Auk. 

126,700 

21,200 

150,900 

126,700 

21,200 

150,900 

122,300 

23,400 

145,700 

Sept. 

120,000 

10,900 

136,900 

120.000 

16,900 

136,900 

115,800 

16,800 

132,600 

Oct. 

113,400 

26,500 

139,000 

113,400 

20,500 

139,900 

109,500 

26,100 

135,600 

Nov. 

110,300 

77.900 

188,200 

110,300 

77.900 

188,200 

106,500 

80.700 

187,200 

Deo. 
Total  or 
average 

109,400 

100,600 

210.000 

109,400 

100.600 

210,000 

105,600 

104.400 

210,000 

113,400 

34,900 

148,300 

113.400 

35.000 

148,400 

109,400 

30,400 

139,800 

*Total  primary  power  productioD  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OF   FLOODS   BY    RESERVOIRS. 


283 


VOIR  ON  SACRAMENTO  RIVER. 

BOTH  WITH  AND  WITHOUT  FLOOD  CONTROL. 

la,  2a  and  4a. 

mary,  see  Table  5,  page  1 16.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.P.  =0.80. 


Operating  primarily  for  irrigation 

witli  incidental  power  generation 

Seasonal  irrigation  yield  4,276.000  acre-feet.     (Deficiency  in  supply  one  year  in 

ten, 

no  deduction  for  downstream  prior  rights). 

Average  power  yield  in  kilowatts  (Load  factor^!. 00) 

Coordinated  with  flood  control 

by  reservoir  operating  diagram 

Year  and 

Without  flood  control 

Maximum  controlled  flow 
at  Red  Bluff  125,000  sec.-ft. 

month 

Maximum  reservoir  space 

required  454,000  acre- 

Feet 

Primary 

Secondary 

Total 

Primary 

Secondary 

Total 

1896 

0 

89,900 

89,900 

0 

99,100 

99,100 

Jan. 

0 

199,400 

199,400 

0 

104,000 

104,000 

Feb. 

0 

225,300 

225,300 

0 

134,900 

134,900 

Mar. 

0 

275,800 

275,800 

0 

275,800 

275,800 

April 

0 

280,000 

280,000 

0 

280,000 

280,000 

May 

0 

280,000 

280,000 

0 

280,000 

280,000 

.Tune 

0 

280,000 

280,000 

0 

280,000 

280,000 

•luly 

0 

280,000 

280,000 

0 

280,000 

280,000 

Aug. 

0 

176,100 

176,100 

0 

176,100 

176,100 

Sept. 

0 

56,200 

56,200 

0 

56,200 

56,200 

Oct. 

0 

0 

0 

0 

0 

0 

Nov, 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 

0 

178,400 

178,400 

0 

164,000 

164,000 

average 
1897 

0 

59,800 

59,800 

0 

195,700 

195,700 

Jan. 

0 

280,000 

280,000 

0 

276,000 

276,000 

Feb. 

0 

254.600 

254,600 

0 

171,600 

171,600 

Mar. 

0 

280,000 

280,000 

0 

242,100 

242.100 

April 

0 

280,000 

280,000 

0 

280,000 

280.000 

May 

0 

280,000 

280,000 

0 

280,000 

280,000 

June 

0 

280,000 

280,000 

0 

280,000 

280,000 

July 

0 

264,400 

264,400 

0 

264,400 

264,400 

Aug. 

0 

152,400 

152,400 

0 

152,400 

152,400 

Sept. 

0 

48,000 

48,000 

0 

48,000 

48,000 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

0 

180,800 

180,800 

0 

181,900 

181,900 

1898 

0 

0 

0 

0 

0 

0 

Jan. 

0 

0 

0 

0 

0 

0 

Feb. 

0 

17,300 

17,300 

0 

17,300 

17,300 

Mar. 

0 

91,000 

91,000 

0 

91,000 

91,000 

April 

0 

275,000 

275,000 

0 

275,000 

275,000 

May 

0 

280,000 

280,000 

0 

280,000 

28,000 

June 

0 

260,200 

260,200 

0 

260,200 

260,200 

July 

0 

162,000 

162,000 

0 

162,000 

102,000 

A.ig. 

0 

0 

0 

0 

0 

0 

Sept. 

0 

0 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 

Tnf  al  nr 

0 

91,200 

91,200 

0 

91,200 

91,200 

average 
1899 

0 

0 

0 

0 

0 

0 

Jan. 

0 

0 

0 

0 

0 

0 

Feb. 

0 

15,900 

15,900 

0 

15,900 

15,900 

Mar. 

0 

89,300 

89,300 

0 

89,300 

89,300 

April 

0 

272,400 

272,400 

0 

272,400 

272,400 

May 

0 

280,000 

280,000 

0 

280,000 

280,000 

June 

0 

252,000 

252,000 

0 

252,000 

2.52,000 

July 

0 

146,100 

146,100 

0 

146,100 

146,100 

Aug. 

0 

0 

0 

0 

0 

0 

Sept. 

0 

0 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

0 

88,700 

88,700 

0 

88.700 

88,700 

2«4 


WATER  RESOURCES  OF    CALIFORNIA. 


Height  of  dam  420  feet. 


TABLE  5a  (Continued).     KENNETT 

SUMMARY  OF  POWER  YIELD  BY  MONTHS 

Summary  of  Tables 
(For  corresponding  yearly  sum 
Capacity  of  reservoir  2,940,000  acre-feet. 


Operating  primarily  for  power  generation  with  incidental  irrigation 

Average 

power  yield 

in  kilowatts  (Load  factor=0.75) 

Coordinated  with  flood  control 

With  flood  control,  holding 

Year  and 

by  reservoir  operating  diagram 

maximum  reservoir  space 

month 

Wit! 

out  flooil  CO 

,     . 

Maximum  oontroll 

d  flow 

require 

i  (454,000  ac 

.-ft.)  in 

at  Red  Bluff  125,00C 

sec.-ft. 

reserve  throughout  flood  season 

Maximum  reservoir  space 

Maximum  controlled  flow 

required  454,000  acre-feet 

at  Red  Bluff  125,00C 

sec.-ft. 

'Primary 

Secondary 

Total 

♦Primary 

Secondary 

Total 

♦Primary 

Secondary 

Total 

1900 

Jan. 

97.400 

103,500 

200,900 

97,400 

110,900 

208,300 

04,100 

112,900 

207.000 

Feb. 

101.900 

62,500 

164,400 

101,900 

22,000 

123,900 

98,500 

64,900 

163.400 

Mar. 

104,200 

102,400 

206,600 

104,200 

43,800 

148,000 

100,500 

104.200 

204.700 

April 

109,000 

80,300 

189,300 

109,000 

33,900 

142,900 

105,300 

20,700 

126.000 

May 

117,500 

46,600 

164,100 

117,500 

46,000 

164,100 

113,300 

0 

113,300 

June 

124,200 

4,900 

129,100 

124,200 

4,900 

129,100 

119,700 

0 

119,700 

July 

125,400 

14,800 

140,200 

125,400 

14,800 

140,200 

121,100 

14,700 

135,800 

Aug. 

126.700 

17,900 

144,600 

126,700 

17,900 

144,600 

122,300 

18,100 

140,400 

Sept. 

120,000 

18,800 

138,800 

120,000 

18,800 

138,800 

115,800 

18.500 

134.300 

Oct. 

113,400 

49,200 

162,600 

113,400 

49,200 

162,600 

109,500 

48,.500 

158,000 

Nov. 

110,300 

59,700 

170,000 

110,309 

59,700 

170,000 

106,500 

61,900 

168,400 

Dec. 
Total  or 
average 

109.400 

89,000 

198,400 

109,400 

89,000 

198,400 

105,600 

99,200 

204.800 

113,400 

54,200 

167,600 

113,400 

42,900 

156,300 

109,400 

47,100 

156,500 

1901 

Jan. 

97,400 

3',),90O 

137,300 

97,400 

101,600 

199,000 

94,100 

115,900 

210,C0D 

Feb. 

101,900 

101.200 

206,100 

101,900 

99,400 

201,300 

98,500 

105.830 

205,300 

Mar. 

104,200 

103,800 

208,000 

101,200 

52,400 

156,600 

100,500 

108,000 

20l).500 

April 

109.000 

51,000 

163,000 

109,000 

0 

109,000 

105,300 

15,40) 

120,700 

May 

117,500 

51,100 

168,600 

117,500 

28,500 

1 16,009 

113,300 

0 

113,300 

June 

124,200 

1,800 

126,000 

121,200 

1.800 

126,000 

119.700 

0 

119.700 

July 

125,400 

14,200 

139,600 

125,400 

14.200 

131,600 

121.100 

0 

121,100 

Aug. 

126,700 

17.100 

143.800 

120,700 

17,100 

143,800 

122.300 

0 

122.300 

Sept. 

120.000 

18.200 

1.38.200 

120.000 

18,200 

138,200 

115,800 

20,600 

136,400 

Oct. 

113,400 

11,400 

121.800 

113.100 

11,400 

124,800 

109,500 

ii,3no 

12;),800 

Nov. 

110.300 

42.5')0 

152  800 

110,300 

42,500 

152,800 

106,509 

43,300 

149,800 

Dec. 

Tntil  nr 

109,400 
1 13 ,400 

100,600 

210,000 

109,400 

100,600 

210,000 

105,600 

101,403 

210,000 

average 

40.300 

159,700 

113.400 

40,400 

1,53,800 

109,400 

43,400 

152,800 

1902 

Jan. 

97,400 

0 

97,400 

97,100 

0 

97,400 

94,100 

0 

94,100 

Feb. 

101,900 

69,300 

171,2(10 

101,900 

77,100 

179,000 

98,500 

79.800 

178,300 

Mar. 

101,200 

105,800 

210,001) 

101.200 

75,300 

179,500 

100,,500 

109,500 

210.000 

April 

109,000 

101.000 

210,000 

109,000 

81.500 

190,500 

105,300 

73,500 

178,800 

May 

117,,500 

91.400 

208.900 

117,.500 

91.400 

208,900 

113,300 

96.700 

210,000 

June 

124.200 

71,700 

195,900 

121,200 

71.700 

195,900 

119,700 

90,300 

210,000 

July 

125  400 

29,000 

151,400 

125,400 

29,000 

151,400 

121.100 

78.800 

199.900 

Aug. 

126,700 

28,400 

1.55,100 

126,700 

28,400 

155,100 

122,300 

27.800 

150.100 

Sept. 

120.000 

11,400 

131,400 

120,000 

11,400 

131,400 

115,800 

11.400 

127.200 

Oct. 

113,400 

19,.500 

132,900 

113,400 

19,500 

132,900 

109,500 

19,200 

128,700 

Nov. 

110,300 

81.100 

191,400 

1 10,300 

81,100 

191,400 

106,500 

81,300 

190,800 

Dec. 

Tntjil  nr 

109,400 

100,000 

210,000 

109,400 

100,600 

210,000 

105,600 

101.400 

210.000 

A  UbUI  Ul 

average 

113,400 

58,900 

172,300 

113,400 

55,300 

168,700 

109,400 

64.500 

173,900 

1903 

Jan. 

97,400 

90,300 

187,700 

97,400 

106,900 

201, .300 

94.100 

89,500 

183,600 

Feb. 

101,900 

108,100 

210,000 

101,900 

100,100 

202,000 

98,500 

111,500 

210,000 

Mar. 

104.200 

105,800 

210.000 

10-1,200 

99,600 

203,800 

100,500 

109.500 

210,000 

April 
May 

109,000 

101,000 

210,000 

109,000 

98,100 

207,100 

105,300 

41.900 

147,200 

117,.500 

64,700 

182.200 

11 7. ,500 

64,700 

182,200 

113.300 

60.600 

173,900 

June 

124,200 

18,300 

142.500 

121.200 

18,.300 

142,500 

119.700 

18,600 

138.300 

July 

125.400 

19.800 

145.200 

125,400 

19,800 

145,200 

121,100 

19,600 

140.700 

Aug. 

126,700 

16.300 

143,000 

126,700 

16.300 

143.000 

122,300 

16.500 

1.38.800 

Sept. 

120.000 

7,200 

127.200 

120,000 

7,200 

127,200 

115,800 

7.100 

122,900 

Oct. 

113,400 

4,800 

118.200 

113,400 

4.800 

118,200 

109,500 

4.800 

114,300 

Nov. 

1 10.300 

65.600 

175,900 

110,300 

65.600 

175.900 

106.500 

68.200 

174.700 

Dec. 
Total  or 

109,400 

100,600 

210,000 

109,400 

95,300 

201,700 

105,600 

104,400 

210,000 

average 

113,400 

58,200 

171,600 

113,400 

57,800 

171,200 

109,400 

51,100 

163,500 

*Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OP   FLOODS   BY   RESERVOIRS. 


285 


RESERVOIR  ON  SACRAMENTO  RIVER. 

BOTH  WITH  AND  WITHOUT  FLOOD  CONTROL. 

la,  2a  and  4a. 

mary,  see  Table  5,  page  116.) 

Installed  capacity  of  power  plant  400,000  k.v.a.     P.F.  =0.80. 


— 

Operating  primarily  for  irrigation  with  incidental  power  generation 

1 

Seasonal  irrigation  yield  4,276,000  acre-feet.    (Deficiency  in  supply  one  year  in  ten,                           | 

no 

deduction  for  downstream  prior  rights). 

Average 

power  yield  in  kilowatts  (Load  factor=1.00) 

Coordinated  with  flood  control 

by  reservoir  operating  diagram 

Year  and 

Without  flood  control 

Maximum  controlled  flow 
at  Red  Bluff  125,000  sec.-ft. 

month 

Maximum  reservoir  space 

required  454,000  acre-feet 

Primary 

Secondary 

Total 

Primary 

Secondary 

Total 

1900 

0 

0 

0 

0 

73,800 

73,800 

JaD. 

0 

57,300 

57,300 

0 

125,100 

125,100 

Feb. 

(1 

247,400 

247,400 

0 

137,400 

137,400 

Mar. 

0 

197,800 

197,800 

0 

170,600 

170,600 

April 

0 

280,000 

280,000 

0 

280,000 

280,000 

May 

0 

280,000 

280,000 

0 

280,000 

280,000 

June 

0 

280,000 

280,000 

0 

280,000 

280,000 

July 

0 

232,500 

233,500 

0 

232,500 

232,500 

Aug. 

n 

124,400 

124,400 

0 

124,400 

124,400 

Sept. 

0 

38,200 

38,200 

0 

38,200 

o8,200 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 

0 

145,500 

145,500 

0 

145,300 

145,300 

a\ erage 
1901 

0 

0 

0 

0 

0 

0 

Jan. 

0 

89,700 

89,700 

0 

214,700 

214,700 

Feb. 

0 

248,800 

218,800 

0 

159,100 

159,100 

Mar. 

0 

165,000 

165,000 

0 

105,000 

105,000 

April 

0 

280,000 

280,000 

0 

280,009 

280,000 

May 

0 

280,000 

280,000 

0 

280,000 

280,000 

June 

0 

280.000 

280,000 

0 

280,030 

280,000 

July 

0 

230,900 

230,900 

0 

230,900 

230,900 

Aug. 

1) 

123,100 

123,100 

0 

123,100 

123,100 

Sept. 

(1 

35,900 

35.900 

0 

35,900 

35,900 

Oct. 

1) 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec 
Total  or 

0 

144,900 

144,900 

0 

142,000 

142,000 

average 
1902 

0 

0 

0 

0 

0 

0 

Jan. 

0 

110.100 

110,100 

0 

149,600 

149,600 

Feb. 

0 

273,700 

273,700 

0 

218,000 

218.000 

Mar. 

0 

277.200 

277,200 

0 

241,500 

241.500 

April 

0 

280,000 

280,000 

0 

280,000 

280.000 

May 

0 

280,000 

280,000 

0 

280,000 

280,000 

June 

II 

280.000 

280,000 

0 

280,000 

280.000 

July 

II 

280,000 

280,000 

0 

280,000 

280.000 

Aug. 

II 

160,600 

160,600 

0 

160,600 

160.600 

Sept. 

n 

50,000 

50,000 

0 

50.000 

50,000 

Oct. 

I) 

0 

0 

0 

0 

0 

Nov 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

0 

166,300 

166,300 

0 

161,600 

161,600 

1903 

II 

63,000 

63,000 

0 

178,800 

178.800 

Jan. 

1) 

265,500 

265.500 

0 

237,600 

237,600 

Feb. 

II 

280,000 

280,000 

0 

252,000 

252.000 

Mar. 

0 

266.400 

266,400 

0 

253,900 

253.900 

April 

0 

280,000 

280.000 

0 

280,000 

280,000 

May 

II 

280.000 

280.000 

0 

280,000 

280,000 

June 

II 

280.000 

280,000 

0 

280,000 

280,000 

July 

0 

212.700 

242.700 

0 

242,700 

212.700 

Aug. 

0 

131,700 

131.700 

0 

131,700 

131.700 

Sept. 

0 

38,300 

38,300 

0 

38,300 

38,300 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 

1 

Total  or 
average 

0 

176,700 

176,700 

0 

181,000 

181,000 

286 


WATER  RESOURCES   OF    CALIFORNIA. 


Height  of  dam  420  feet. 


TABLE  5a  (Continued).     KENNETT 

SUMMARY  OF  POWER  YIELD  BY  MONTHS 

Summary  of  Tables 

(For  corresponding  yearly  sum 
Capacity  of  reservoir  2,940,000  acre-feet. 


Operating  primarily  for  power  generation  with  incidental  irrigation 

Average 

power  yield 

in  kilowatts  (Load  factor=0.75) 

Coordinated  with  flood  control 

With  flood  control,  holding 

Year  and 

by  reservoir  operating  diagram 

maximum  reservoir  space 

month 

\\^it,b"iit  fl""''  «nn(rnl 

Maximum  controlled  flow 

required  (454,000  ac 

.-ft.)  in 

at  Red  Bluff  125,00C 

sec.-ft. 

reserve  tl: 

roughout  flood  season 

Maximum  reservoir  space 

Maximum  controlled  flow 

required  454,000  acre-feet 

at  Red  Bluff  125,000  sec-ft. 

•Primary 

Secondary 

Total 

•Primary 

Secondary 

Total 

♦Primary 

Secondary 

Total 

1904 

Jan. 

97.400 

80,000 

177,400 

97,400 

94,500 

191.900 

94,100 

82,300 

176,400 

Feb. 

98.400 

92,400 

190,800 

98,400 

70,500 

168,900 

95,100 

89,400 

184.500 

Mar. 

101.200 

105  800 

210,000 

104,200 

105,800 

210,000 

100.500 

109.500 

210.000 

April 

109,000 

101.000 

210,000 

109,000 

101,000 

210,000 

105,-300 

84.000 

189,300 

May 

117,.500 

92.500 

210,000 

117,500 

92.500 

210,000 

113,.300 

96,700 

210.000 

.Tunc 

124.200 

85,800 

210,000 

124,200 

85,800 

210,000 

119,700 

90,300 

210,000 

.July 

12,5,400 

84,600 

210,000 

125,400 

84,600 

210,000 

121.100 

88.900 

210.000 

AuE 

126.700 

54,600 

181,300 

126.700 

54,600 

181,300 

122..300 

87,700 

210,009 

Sept. 

120,000 

48,300 

168.300 

120.000 

48,300 

168,300 

115.800 

74.600 

190.400 

Oct. 

113,400 

81,900 

195.300 

113,400 

81,900 

I95,.300 

109,500 

100,500 

210,000 

Nov. 

110,300 

99,700 

210.000 

110,,300 

99,700 

210.000 

105,500 

101.500 

208,000 

Dec. 

109,400 

100,600 

210,000 

109,400 

100.600 

210,000 

105,600 

101.500 

207.100 

Total  or 

average 

113.000 

85,600 

198,600 

113,000 

85,100 

198,100 

103,100 

92,300 

201,400 

1905 

Jan. 

07,400 

36,300 

133,700 

97,400 

72,600 

170,000 

91,100 

63.600 

157,700 

Feb. 

101,900 

108,100 

210,000 

101,900 

103,600 

205,500 

98,500 

111,500 

210,000 

Mar. 

104.200 

105,800 

210,000 

104,200 

98,400 

202,600 

100,500 

109,500 

210.000 

April 

109,000 

101,000 

210.000 

109,000 

101,000 

210,000 

105,303 

45,600 

150,900 

May 

117,.500 

87,600 

205.100 

117,500 

87,600 

205.100 

113,.3O0 

88.200 

201,500 

June 

124,200 

56,100 

180,300 

124,200 

56.100 

180.300 

119,700 

73,800 

193.500 

July 

12.5,400 

35,500 

160,900 

125,400 

35.500 

160,900 

121,100 

34.900 

15S.OO0 

Aug. 

126,700 

29,200 

155,900 

126.700 

29,200 

1.55.900 

122,300 

28,800 

151,100 

Sept. 

120  000 

21.700 

141,700 

120,000 

21,700 

141,700 

115.800 

21.400 

137.200 

Oct. 

113  400 

13,800 

127,200 

113,400 

13,800 

127,200 

109.500 

13.700 

123.200 

Nov. 

110,300 

21,900 

132,200 

110.300 

21,900 

132,200 

106,500 

21,800 

128,300 

Dec. 
Total  or 

109.400 

0 

109,400 

109,400 

0 

109.400 

105,600 

25,500 

131,100 

average 

113,400 

51,000 

164,400 

113.400 

.53,100 

166.500 

109,400 

52,800 

162,200 

1906 

.Ian. 

97,400 

0 

97,400 

97,400 

21,600 

119,000 

94,100 

44,400 

138.500 

Fob. 

101,900 

64,700 

166.600 

101,900 

63,700 

165,600 

98,500 

95,800 

194.300 

Mar. 

104,200 

105,800 

210,000 

104,200 

98,900 

203,100 

100,500 

109,500 

210,000 

April 
May 

109,000 

101,000 

210,000 

109,000 

101,000 

210,000 

105,300 

61,500 

166,800 

117,500 

92,500 

210,000 

117,500 

92,500 

210.000 

113,300 

96,700 

210,000 

June 

124,200 

85,800 

210,000 

124,200 

85,800 

210.000 

119,700 

90,300 

210.000 

July 

125,400 

84,600 

210,000 

125,400 

84,600 

210,000 

121,100 

88,900 

210,000 

Aug. 

126.700 

61.700 

188.400 

126,700 

61,700 

188,400 

122,300 

87,700 

210,000 

Sept. 

120,000 

37,800 

157.800 

120.000 

37,800 

157.800 

115,800 

72,200 

188,000 

Oct. 

113,400 

26.100 

139.500 

113,400 

26,100 

139,500 

109,500 

25,700 

135.200 

Nov. 

110,300 

32,800 

143.100 

110,300 

32,800 

143,100 

106,500 

32.900 

139,400 

Deo. 
Total  or 

109,400 

74.300 

183,700 

109,400 

74,300 

183,700 

105,600 

84,700 

190,300 

average 

113,400 

63,900 

177,300 

113,400 

65,100 

178,500 

109,400 

74,100 

183,500 

1907 

Jan. 

97,400 

18,500 

115,900 

97,400 

100,300 

197,700 

94,100 

100.900 

195,000 

I'eb. 

101,900 

108,100 

210,000 

101,900 

108,100 

210.000 

98,500 

111,500 

210,000 

Mar. 

104,200 

105,800 

210,000 

104,200 

105,800 

210,000 

100,500 

109,500 

210,000 

April 
May 

109,000 

101,000 

210,000 

109,000 

101,000 

210,000 

105,300 

84,000 

189,300 

117,500 

92,500 

210,000 

117,500 

92,.500 

210.000 

113,300 

96,700 

210.000 

June 

124.200 

78,200 

202,400 

124,200 

78,200 

202,400 

119.700 

90,300 

210.000 

July 

125,400 

62.600 

188,000 

125,400 

62,600 

188,000 

121,100 

88.900 

210.000 

Aug. 

126,700 

52,000 

178,700 

126,700 

52,000 

178,700 

122,300 

83,600 

205.900 

Sept. 

120,000 

40,300 

160,300 

120,000 

40,300 

160,300 

115.800 

39,300 

155,100 

Oct. 

11.3,400 

30,100 

143.500 

11.3,400 

30,100 

143,500 

109,500 

29,700 

139.200 

Nov. 

110,300 

33,300 

143,600 

110,300 

33,300 

143,600 

106,500 

32,900 

139.400 

Dec. 
Total  or 

109.400 

55,100 

164,500 

109,400 

55,100 

164,500 

105,600 

76,200 

181,800 

average 

113,400 

64,500 

177.900 

113,400 

71,400 

184,800 

109,400 

78,500 

187.900 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


TPIE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


287 


RESERVOIR  ON  SACRAMENTO  RIVER. 

BOTH  WITH  AND  WITHOUT  FLOOD  CONTROL, 
la,  2a  and  4a. 

mary,  see  Table  5,  page  1 16.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.P.  =  0.80. 


Operating  primarily  for  irrigation  with  incidental  power  generation 

Ssasonal  irrigation  yield  4,276,000  aore-feet.     (Defioiency  in  supply  one  year  in 

ten. 

no 

dsluotion  for  downstream  prior  rights). 

Average  power  yield  in  kilowatts  (Load  factor^l.OO) 

Coordinated  with  flood  control 

by  reservoir  operating  d 

agram 

Year  and 

Without  flood  control 

Maximum  controlled  flow 
at  Red  Bluff  125,000  sec.-ft. 

month 

Maximum  reservoir  space 

required  454,000  acre- 

feet 

Primary 

Secondary 

Total 

Primary 

Secondary 

Total 

1904 

0 

0 

0 

0 

0 

0 

Jan. 

0 

125,100 

125,100 

0 

155,300 

155,300 

Feb. 

0 

280,000 

280,000 

0 

280,000 

280,000 

Mar. 

n 

280,000 

280,000 

0 

280,000 

280,000 

April 

0 

280,000 

280,000 

0 

280,000 

280,000 

May 

n 

280,000 

280,000 

(1 

280,000 

280,000 

June 

n 

280,000 

280,000 

0 

280,000 

280,000 

July 

0 

280,000 

280,000 

0 

280,000 

280,000 

Aug. 

0 

178,300 

178,300 

0 

178,.300 

178,300 

Sept. 

n 

58,000 

."8,000 

0 

58,600 

58,600 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 

0 

170,200 

170,200 

0 

172,600 

172,600 

average 
1905 

0 

132,100 

132,100 

0 

222.700 

222,700 

Jan. 

0 

278,300 

278,300 

0 

268,600 

268,600 

Feb. 

0 

273,500 

273,500 

0 

250,900 

250,900 

Mar. 

0 

270,800 

270,800 

0 

270.800 

270,800 

April 

n 

280,000 

280,000 

0 

280,000 

280,000 

May 

0 

280.000 

280,000 

0 

280,000 

280.000 

June 

0 

280,000 

280,000 

0 

280,000 

280,000 

July 

0 

270,200 

270,200 

0 

270,200 

270,200 

Aug. 

0 

153,800 

153,800 

0 

153,800 

153,800 

Sept. 

n 

■17,600 

47.600 

0 

47,600 

47,600 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 

0 

188,300 

188,300 

0 

193,300 

193,300 

average 
1906 

0 

0 

0 

0 

0 

0 

Jan. 

n 

0 

0 

0 

53,300 

53,300 

Feb. 

0 

280,000 

280,000 

0 

257,900 

257,900 

Mar. 

0 

280,000 

280,000 

0 

280,000 

280,000 

April 

0 

280,000 

280,000 

0 

280,000 

280,000 

May 

0 

280,000 

280,000 

0 

280,000 

280,000 

June 

0 

280,000 

280,000 

0 

280,000 

280,000 

July 

n 

280,000 

280,000 

0 

280,000 

280,000 

Aug. 

0 

186,000 

186,000 

0 

186,000 

186,000 

Sept. 

0 

59,300 

59,300 

0 

59,300 

59,300 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 

161,500 

161,500 

0 

163,700 

163,700 

average 

0 

1907 

0 

59,100 

59,100 

0 

219,600 

219,600 

.Ian. 

0 

280,000 

280,000 

0 

280,000 

280,000 

Feb. 

0 

280,000 

280,000 

0 

278,600 

278,600 

Mar. 

•     0 

280,000 

280,000 

0 

280,000 

280,000 

April 

0 

280,000 

280,000 

0 

280,000 

280,000 

May 

n 

280,000 

280,000 

0 

280,000 

280,000 

June 

0 

280,000 

280,000 

0 

280,000 

280,000 

July 

(1 

280,000 

280,000 

0 

280,000 

280,000 

Aug. 

0 

169,700 

169,700 

0 

169,700 

169,700 

Sept. 

n 

53,900 

53,000 

0 

53,900 

53,900 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

0 

186,200 

186,200 

0 

199,700 

199,700 

288 


WATER  RESOURCES  OP   CALIFORNIA. 


Height  of  dam  420  feet. 


TABLE  5a  (Continued).     KENNETT 

SUMMARY  OF  POWER  YIELD  BY  MONTHS 

Summary  of  Tables 

(For  corresponding  yearly  sum 
Capacity  of  reservoir  2,940,000  acre-feet. 


Operating  primarily  for  power  generation  with  incidental  irrigation 

Average 

power  yield 

in  kilowatts  (Load  facto 

r=0.75) 

Coordinated  with  flood  control 

With  flood  control,  holding 

Year  and 

by  reservoir  operating  diagram 

maximum  reservoir  space 

month 

Tir:*i ,.A  a^ 1  ..»n4.-»1 

Maximum  controlled  flow 

required  (454,000  a( 

.-ft.)  in 

witr 

"""  """"  ''W 

UllUl 

at  Red  Bluff  125,000  sec.-ft. 

reserve  throughout  flood  season 

Maximum  reservoir  space 

Maximum  controlled  flow 

required  454,000  acre-feet 

at  Red  Bluff  125,000  sec.-ft. 

•Primary 

Secondary 

Total 

•Primary 

Secondary 

Total 

•Primary 

Secondary 

Total 

1908 

Jan. 

97,400 

20,200 

117,600 

97,400 

38,300 

135,700 

94,100 

48,500 

142,600 

Feb. 

98,400 

111,600 

210,000 

98,400 

90,800 

189,200 

95,100 

111,600 

206,700 

Mar. 

104.200 

105,800 

210,000 

104,200 

36,300 

140,500 

100,500 

109,400 

209,900 

April 

109,000 

98,100 

207,100 

109,000 

58  300 

167,300 

105,300 

20,700 

126,000 

May 

m.hoo 

79,600 

197,100 

117,500 

79,600 

197,100 

113,300 

59,000 

172,300 

June 

124,200 

45,100 

169,.300 

124.200 

45,100 

169,300 

119,700 

45,100 

164,800 

July 

125,400 

31,600 

157,000 

125,400 

31,600 

157,000 

121,100 

31.200 

1.52,300 

Aug. 

126,700 

26,200 

152,900 

126,700 

26,200 

152,900 

122.300 

25,900 

148.200 

Sept. 

120,000 

20,400 

140,400 

120,000 

20.400 

140,400 

115,800 

20.100 

135,900 

Oct. 

113,400 

19,500 

132,900 

113,400 

19.500 

132,900 

109,500 

19,200 

128,700 

Nov. 

110,300 

33,800 

144,100 

110,300 

33,800 

144,100 

106,500 

33,300 

139,800 

Dec. 

109.400 

5,900 

115,300 

109,400 

5,900 

115,300 

105,600 

32,300 

137,900 

1  U  1.11  Vl 

average 

113,000 

49,500 

162,500 

113,000 

40,200 

153,200 

109,100 

46,200 

155,300 

1909 

Jan. 

97,400 

76,200 

173,600 

97.400 

87,100 

184,500 

94,100 

89,700 

183,800 

Feb. 

101,900 

108,100 

210,000 

101,900 

108,100 

210,000 

98.500 

111,500 

210,000 

Mar 

104,200 

105,800 

210,000 

104,200 

81,700 

185,900 

100,500 

109,500 

210,000 

April 

109,000 

101,000 

210,000 

109,000 

100,100 

209,100 

105,300 

52,500 

157,800 

May 

117.500 

91,.500 

209,000 

117.500 

91,500 

209,000 

113,300 

96,700 

210,000 

June 

124,200 

74,900 

199,100 

124,200 

74,900 

199,100 

119,700 

90,300 

210,000 

July 

125,400 

51,700 

177,100 

125,400 

51,700 

177,100 

121,100 

70,800 

191,900 

Aug. 

120,700 

40,900 

167,600 

120,700 

40.900 

167,600 

122,300 

40,300 

162.600 

Sept. 

120,000 

37,800 

157,800 

120,000 

37,800 

157,800 

115,800 

36,800 

152,600 

Oct. 

113,400 

39,400 

152,800 

113.400 

39,400 

152,800 

109,500 

38.400 

147.900 

Nov. 

110,300 

72,500 

182,800 

110,300 

72,500 

182,800 

106,500 

73,600 

180,100 

Dec. 
Total  or 
average 

109,400 

100,000 

210,000 

109,400 

100,600 

210,000 

105,600 

104,400 

210,000 

113,400 

74,800 

188,200 

113,400 

73,600 

187,000 

109,400 

76,100 

185,500 

1910 

Jan. 

97,400 

29,000 

126,400 

97,400 

57,000 

154,400 

94,100 

93.800 

187,900 

Feb. 

101,900 

108,100 

210.000 

101,900 

62,900 

164,800 

98,500 

111,500 

210,000 

Mar. 

104,200 

105,800 

210.000 

104.200 

100,400 

204,600 

100,500 

109,500 

210,000 

April 

109,000 

101,000 

210,000 

109.000 

101,000 

210,000 

105,300 

38,800 

144,100 

May 

117,500 

.54,400 

171,900 

117,500 

54,400 

171,900 

113,300 

39,400 

152,700 

Juno 

124,200 

20,100 

144.300 

124,200 

20,100 

144,300 

119,700 

20,400 

140,100 

July 

125,400 

29,400 

154,800 

125,400 

29,400 

154,800 

121,100 

20,200 

150,300 

Aug. 

126,700 

29,200 

155,900 

126,700 

29,200 

1,55,900 

122.300 

28,800 

151,100 

Sept. 

120,000 

24,200 

144,200 

120,000 

24,200 

144,200 

115,800 

23,<)O0 

139,700 

Oct. 

113,400 

17,900 

131,300 

11.3.400 

17,900 

131,300 

109,500 

17,700 

127,200 

Nov. 

110,300 

40,300 

150,600 

110,300 

40.300 

150,600 

106,.500 

40,300 

146,800 

Dec. 
Total  or 

109.400 

73.400 

182,800 

109,400 

73,000 

182,400 

105,600 

98,500 

204,100 

average 

113,400 

52.300 

165,700 

113,400 

50,800 

164,200 

109.400 

54,100 

163,500 

1911 

Jan. 

97,400 

0 

97.400 

97,400 

7,300 

104.700 

94,100 

3,800 

97,900 

Feb. 

101.900 

88,100 

190,000 

101,900 

75.000 

176,900 

98,500 

111,500 

210.000 

Mar. 

104,200 

104,400 

208.600 

101,200 

100,900 

205,100 

100.500 

107.700 

208.200 

April 
May 

109,000 

101,000 

210,000 

109,000 

101.000 

210,000 

105,300 

70,000 

175,300 

117,.500 

92.500 

210.000 

117,500 

92.500 

210,000 

113,300 

96,700 

210,000 

June 

124.200 

79,600 

203.800 

124.200 

79,600 

203,800 

119,700 

90.300 

210,000 

July 

125,400 

42.900 

168,300 

125,400 

42,900 

168,300 

121,100 

88,900 

210,000 

Aug. 

126,700 

32.500 

1.59.200 

126.700 

32,500 

159,200 

122,300 

43,500 

165,800 

Sept. 

120,000 

30.700 

150.700 

120,000 

30,700 

150,700 

115,800 

30.600 

146,400 

Got. 

113,400 

24.100 

137.500 

113,400 

24  100 

137,500 

109,500 

23,700 

133,200 

Nov. 

110,300 

26,900 

137,200 

110,300 

26,900 

137,200 

106.500 

28,700 

133.200 

Dec. 
Total  or 

109.400 

0 

109,400 

109,400 

0 

109,400 

105,600 

23,300 

128,900 

average 

113,400 

51,500 

164,900 

113,400 

50.800 

164,200 

109.400 

59,300 

168,700 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OF   FLOODS  BY   RESERVOIRS. 


289 


RESERVOIR  ON  SACRAMENTO  RIVER. 

BOTH  WITH  AND  WITHOUT  FLOOD  CONTROL, 
la,  2a  and  4a. 

mary,  see  Table  5,  page  1 16.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.P.  =  0.80. 


Operating  primarily  for  irrigation 

with  incidental  power  generation 

Seasonal  irrigation  yield  4,276,000  acre-feet.    (Deficiency  in  supply  one  year  in 

ten, 

no  deduction  for  downstream  prior  rights). 

Average  power  yield  in  kilowatts  (Load  factor=1.00) 

Coordinated  with  flood  control 

by  reservoir  operating  diagram 

Year  and 

Without  flood  control 

Maximum  controlled  flow 
at  Red  Bluff  125,000  sec.-ft. 

month 

Maximum  reservoir  space 

required  454,000  acre- 

feet 

Primary 

Secondary 

Total 

Primary 

Secondary 

Total 

1908 

0 

0 

0 

0 

18,100 

18,100 

Jan. 

0 

213,100 

213,100 

0 

232,200 

232,200 

Feb. 

0 

264,300 

264,300 

0 

128,900 

128,900 

Mar. 

0 

227,900 

227,900 

0 

207,800 

207,800 

April 

0 

280,000 

280,000 

0 

280,000 

280,000 

May 

0 

280,000 

280,000 

0 

280,000 

280,000 

June 

0 

280,000 

280,000 

0 

280,000 

280,000 

July 

0 

258,500 

258,500 

0 

258,500 

2.58,500 

Aug. 

0 

146,000 

146,000 

0 

146,000 

146,000 

Sept. 

0 

44,800 

44,800 

0 

44,800 

44,800 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

0 

166,000 

166,000 

0 

155,900 

155,900 

1909 

0 

117,100 

117,100 

0 

128,600 

128,600 

Jan. 

0 

280,000 

280,000 

0 

280,000 

280,000 

Feb. 

0 

280,000 

280,000 

0 

225,800 

225,800 

Mar. 

0 

280,000 

280,000 

0 

275,300 

275,300 

April 

0 

280,000 

280,000 

0 

280,000 

280,000 

May 

0 

280,000 

280,000 

0 

280,000 

280,000 

June 

0 

280,000 

280,000 

0 

280,000 

280,000 

July 

0 

280,000 

280,000 

0 

280,000 

280.000 

Aug. 

0 

163,100 

163,100 

0 

163,100 

163,100 

Sept. 

0 

51,700 

51,700 

0 

51,700 

51,700 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

0 

190,400 

190,400 

0 

186,400 

186,400 

1910 

0 

0 

0 

0 

63,200 

63,200 

Jan. 

0 

257,400 

257,400 

0 

190,300 

190.300 

Feb. 

0 

280,000 

280,000 

0 

265,700 

265,700 

Mar. 

0 

264,900 

264,900 

0 

264,900 

264,900 

April 

0 

280,000 

280,000 

0 

280,000 

280,000 

May 

0 

280.000 

280,000 

0 

280,000 

280,000 

June 

0 

280,000 

280,000 

0 

280,000 

280,000 

July 

0 

242,600 

242,600 

0 

242,600 

242,600 

Aug. 

0 

135,400 

135,400 

0 

135,400 

135,400 

Sept. 

n 

41,000 

41,000 

0 

41,000 

41,000 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

0 

171,100 

171,100 

0 

170,100 

170,100 

1911 

0 

0 

0 

0 

0 

0 

Jan. 

0 

0 

(1 

0 

75,600 

75,600 

Feb. 

0 

237,000 

237,000 

0 

263,200 

263,200 

Mar. 

0 

280,000 

280,000 

0 

278,300 

278,300 

April 

0 

280,000 

280,000 

0 

280,000 

280,000 

May 

0 

280.000 

280.000 

0 

280,000 

280,000 

June 

0 

280.000 

280,000 

0 

280,000 

280,000 

July 

0 

280,000 

280,000 

0 

280.000 

280,000 

Aug. 

0 

165,600 

165,600 

0 

165,600 

165,600 

Sept. 

0 

52,300 

52,300 

0 

52,300 

52,300 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

0 

155,500 

155,500 

0 

163,400 

163,400 

290 


WATER  RESOURCES  OF    CALIFORNIA. 


Height  of  dam  420  feet. 


TABLE  5a  (Continued).     KENNETT 

SUMMARY  OF  POWER  YIELD  BY  MONTHS 

Summary  of  Tables 

(For  corresponding  yearly  sum 
Capacity  of  reservoir  2,940,000  acre-feet. 


Operating  primarily  for  power  generation  with  incidental  irrigation 

Average  power  yield 

in  kilowatts  (Load  factor=0.75) 

Coordinated  with  flood  control 

With  flood  control,  holding 

Year  and 

by  reservoir  operatinE  diagram 

maximum  reservoir  space 

month 

WTii 

L...1  n_-j  ._ 

ntrol 

Maximum  controlled  flow 

require 

d  (454,000  a( 

.-ft.)  in 

Wltuuui  uuuu  uu 

at  Red  Bluff  125,000  sec.-ft. 

reserve  throughout  flood  season 

Maximum  reservoir  space 

Ma.iiimum  controlled  flow 

required  454,000  acre-feet 

at  Red  Bluff  125.000  sec.-ft. 

•Primary 

Secondary 

Total 

♦Primary 

Secondary 

Total 

•Primary 

Secondary 

Total 

1912 

Jan. 

97,400 

0 

97,400 

97.400 

0 

97,400 

94,100 

0 

94,100 

Feb. 

98,400 

0 

98.400 

98.400 

0 

98.400 

95,100 

17,701 

112,800 

Mar. 

104,200 

50.300 

151. .500 

104,200 

50,300 

151.500 

100.500 

109,500 

210.000 

April 

109.000 

80,000 

189.000 

109,000 

80,000 

189  000 

105.300 

15.100 

120,700 

May 

117,500 

91,900 

209,400 

117,500 

91,900 

209,400 

]1.3,.300 

87.100 

200,400 

June 

124.200 

09,000 

193.200 

124.200 

69,000 

193,200 

119,700 

90.300 

210,000 

July 

125,400 

37.500 

162  900 

125,400 

37.500 

162,900 

121,100 

76.300 

197.400 

Aug 

126,700 

30  000 

156.700 

126.700 

30.000 

156.700 

122,300 

29.600 

151.900 

Sept. 

120.000 

36.000 

156.000 

120,000 

36.000 

156,000 

115.800 

35.100 

150,900 

Oct. 

113.400 

15,900 

129,300 

113,400 

15.900 

129,300 

101.501 

15,600 

125.100 

Nov. 

110..300 

87,100 

197,400 

1 10.300 

87,100 

197.400 

106,500 

90.100 

196.600 

Dec. 

109.400 

64,500 

173,900 

109,400 

64,500 

173.900 

105.600 

85.800 

191,400 

Total  or 
average 

113,000 

46,900 

159,900 

113,000 

46,900 

159,900 

109,100 

51..500 

163,600 

1913 

Jan. 

97,400 

0 

97,400 

97.400 

45,000 

142.400 

94.100 

39.800 

133,900 

Feb. 

101,900 

6,400 

108.300 

101,900 

7,600 

109.500 

98,500 

76.310 

174.800 

Mar. 

104,200 

76,200 

180,400 

104,200 

0 

104.200 

100.500 

80.100 

180,600 

April 
May 

1 09.000 

10 ',000 

210,000 

109,000 

87,600 

196.600 

105.300 

41.100 

146.400 

117.500 

85.500 

203,000 

117,500 

85.500 

203.000 

113,300 

89,000 

202,300 

June 

124,200 

36,800 

161.000 

124,200 

36,800 

161,000 

119,700 

36.800 

156.500 

July 

125,400 

32,800 

158,200 

125,400 

32.800 

158,200 

121,100 

32.900 

154.000 

Aug. 

126,700 

27.600 

151,309 

126.700 

27.600 

154,300 

122,.300 

27.200 

149.500 

Sept. 

120,000 

14  000 

134,000 

120;000 

14.000 

134,000 

115.800 

13.900 

129.700 

Oct. 

113.400 

6.000 

119,400 

113,400 

6.000 

119,400 

109.500 

6.000 

115,500 

Nov. 

1I0..300 

43,600 

153,900 

110,300 

43,600 

153,900 

106,500 

43.800 

150,.300 

Dec. 
Total  or 
average 

109,400 

72,900 

182,300 

109.400 

72,900 

182,300 

105,600 

90,500 

196,100 

113,400 

42,100 

I.55,.500 

11.3,400 

38,500 

151,900 

109.400 

48,000 

157,400 

1914 
Jan. 

97,400 

105,500 

202,900 

97,400 

105,200 

202,600 

94.100 

1 15,P00 

210.000 

Feb. 

101,900 

108,100 

210.0110 

101,900 

108,100 

210.000 

98.500 

111,500 

210,000 

Mar. 

n  1.200 

1()").S0() 

2io.o:io 

101,200 

99,600 

203,800 

100.500 

101.500 

210.000 

April 

100.000 

101.000 

210.000 

lO't.OOO 

100,700 

209.700 

105,300 

81,800 

187.100 

May 

117,500 

92.500 

210,000 

117,500 

92.500 

210,000 

113,300 

96.700 

210.001 

.Tunc 

124200 

85.800 

210.000 

124,200 

85,800 

210.000 

119,700 

90.300 

210.000 

July 

125,400 

51.800 

180,200 

125.400 

51,800 

180.200 

121.100 

88.900 

210.000 

Aug. 

126,700 

.34.100 

160.800 

126,700 

34,100 

160.800 

122.300 

68,400 

190.700 

Sept. 

120,000 

28.800 

148,800 

120,000 

28,800 

148.800 

115,800 

28.500 

141..300 

Oct. 

113.400 

33.2C0 

146,600 

113.400 

33,200 

146.600 

101.500 

32.900 

142.400 

Nov. 

110,300 

31,100 

141,401 

1 10,301 

31,100 

141.400 

lOfi.500 

31. .300 

137.800 

Dec. 
Total  or 
average 

109,400 
113.400 

37.900 

147,301 

109,400 

37.900 

•147.300 

105.600 

63.700 

169,300 

68,000 

181,400 

113,400 

67,400 

180.800 

103.400 

76.500 

185.900 

1016 

Jan. 

97.400 

0 

97,400 

97,400 

40.901 

138.300 

94,100 

14.f01 

109.000 

Feb. 

101,900 

108,100 

210,000 

101,900 

108.100 

210.000 

98.500 

111, .500 

210.000 

Mar. 

101,200 

105.800 

210,000 

101,200 

105,800 

210  000 

100.500 

109.501 

210,000 

April 
May 

109.000 

101,000 

210,000 

109,010 

101,000 

210.011 

105.300 

76,800 

182,100 

117,500 

92.501 

210.000 

117,500 

92.501 

210.000 

113,300 

96.700 

210,000 

June 

121,200 

85,800 

210.000 

121.200 

85.800 

210.010 

119  700 

90,300 

210.000 

July 

125.409 

83.900 

20t.300 

125.401 

83,900 

20'l.301 

121,100 

88.Q01 

210.000 

Aug. 

126,700 

41.701 

168,400 

126,701 

41,700 

1 68.401 

122  301 

87,700 

210,000 

Sept. 

120.001 

24.701 

141,701 

120,000 

21.700 

141,700 

1 15,800 

44,901 

160.701 

Oct. 

11.3.100 

18.701 

132.101 

113.400 

18.700 

132,100 

109.500 

18,400 

127.900 

Nov. 

110.300 

32.401 

1 42,700 

1 10.300 

32.400 

142,700 

106,500 

32,101 

1.38,600 

Dec. 
Total  or 

109.400 

94,900 

201,300 

109.400 

94.900 

204,300 

105.600 

100,100 

205,700 

average 

113.400 

65,500 

178.900 

113.')  00 

69.000 

182,400 

109,400 

72,400 

181.800 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


291 


RESERVOIR  ON  SACRAMENTO  RIVER. 

BOTH  WITH  AND  WITHOUT  FLOOD  CONTROL, 
la,  2a  and  4a. 

mary,  see  Table  5,  page  116.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.P.  =0.80. 


Operating  primarily  for  irrigation 

with  incidental  power  generation 

Seasonal  irrigation  yield  4,276.000  acre-feet.    (Deficiency  in  supply  one  year  in 

ten, 

no  deduction  for  downstream  prior  rights). 

Average  power  yield  in  kilowatts  (Load  factor=1.00) 

Coordinated  with  flood  control 

by  reservoir  operating  diagram 

Year  and 

Without  flood  control 

■    Maximum  controlled  flow 
at  Red  Bluff  125,000  sec.-ft. 

month 

Maximum  reservoir  space 

required  454,000  acre- 

feet 

Primary 

Secondary 

Total 

Primary 

Secondary 

Total 

1912 

0 

0 

0 

0 

0 

0 

Jan. 

0 

0 

0 

0 

0 

0 

Feb. 

0 

23,000 

23,000 

0 

23,000 

23,000 

Mar. 

0 

1M,900 

199,900 

0 

199.900 

199,900 

April 

0 

280,000 

280,000 

0 

280,000 

280,000 

May 

0 

280,000 

280,000 

0 

280,000 

280,000 

June 

n 

280,000 

280,000 

0 

280,000 

280,000 

July 

0 

280,000 

280.000 

0 

280,000 

280,000 

Aug. 

0 

163,600 

163.600 

0 

163,600 

163,600 

Sept. 

0 

51,500 

51,500 

0 

51,500 

51,500 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 

0 

130,200 

130.200 

0 

130,200 

130,200 

average 
1913 

0 

0 

0 

0 

0 

0 

Jan. 

0 

0 

0 

0 

62,500 

62,500 

Feb. 

0 

150,400 

150,400 

0 

91,500 

91.500 

Mar. 

0 

274,300 

274,300 

0 

274,300 

274,300 

April 

0 

280,000 

280.000 

0 

280,000 

280,003 

May 

0 

280,000 

280,000 

0 

280.000 

280,000 

June 

0 

280,000 

280,000 

0 

280,000 

280.000 

July 

0 

260,400 

260,400 

0 

260,400 

260.400 

Aug. 

0 

146,500 

146,500 

0 

146,500 

146.500 

Sept. 

0 

4^,500 

44,500 

0 

44,500 

44,500 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

0 

143,800 

143,800 

0 

143,600 

143,600 

1914 

0 

144,100 

144,100 

0 

171,100 

171,100 

Jan. 

0 

275,700 

275  700 

0 

280.000 

280.000 

Feb. 

0 

280,000 

280,000 

0 

255,800 

255,800 

Mar. 

0 

278,600 

278,600 

0 

273,200 

273,200 

April 

0 

280,000 

280,000 

0 

280.000 

280,000 

May 

0 

280,000 

280,000 

0 

280.000 

280,000 

June 

0 

280,000 

280,000 

0 

280,000 

280.000 

July 

0 

280,000 

280,000 

0 

280.000 

280.000 

Aug. 

0 

168,300 

168.300 

0 

168.300 

168.300 

Sept. 

0 

53,400 

53,400 

0 

53,400 

53,400 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

0 

192,800 

192,800 

0 

192,900 

192,900 

1915 

0 

0 

0 

0 

9,000 

9,000 

Jan. 

0 

269.200 

269,200 

0 

278,100 

278.100 

Feb. 

0 

280,000 

280,000 

0 

271,900 

271,900 

Mar. 

0 

280,000 

280,000 

0 

280,000 

280,000 

April 

0 

280,000 

280,000 

0 

280.000 

280,000 

May 

0 

280,000 

280,000 

0 

280,000 

280,000 

Jane 

0 

280,000 

280,000 

0 

280,000 

280.000 

July 

0 

280,000 

280,000 

0 

280,000 

280,000 

Aug. 

0 

177.500 

177.500 

0 

177,500 

177.500 

Sept. 

0 

56,000 

56,000 

0 

56,000 

56,000 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

0 

181,100 

181,100 

0 

181.900 

181,900 

292 


WATER  RESOURCES  OF   CALIFORNIA. 


Height  of  dam  420  feet. 


TABLE  5a  (Continued).     KENNETT 

SUMMARY  OF  POWER  YIELD  BY  MONTHS 

Summary  of  Tables 

(For  corresponding  yearly  sum 
Capacity  of  reservoir  2,940,000  acre-feet. 


Operating  primarily  for  power  generation  with  Incidental  Irrigation 

Average 

power  yield 

in  kilowatts  (Load  factor 

=0.75) 

Coordinated  with  flood  control 

With  flood  control,  holding 

Year  and 

by  reservoir  operating  diagram 

maximum  reservoir  space 

month 

Without  flood  control 

Maximum  controlled  flow 
at  Red  Bluff  125.000  sec.-ft. 

required  (454,000  ac.-ft.)  in 
reserve  throughout  flood  season 

Maximum  reservoir  space 

Maximum  controlled  flow 

required  454,000  acre-feet 

at  Red  Bluff  125,000 

sec.-ft. 

•Primary 

Secondary 

Total 

•Primary 

Secondary 

Total 

•Primary 

Secondary 

Total 

1916 

Jan. 

97,400 

32,700 

130,100 

97,400 

90,700 

188,100 

94,100 

85,900 

180,000 

Feb. 

98,400 

111,600 

210,000 

98.400 

107,900 

206,300 

95,100 

111,600 

206,700 

Mar. 

104,200 

105,800 

210,000 

104.200 

97.000 

201.200 

100,500 

109,500 

210,000 

April 

109,000 

100,300 

209,300 

109,000 

92,400 

201,400 

105,300 

41,900 

147,200 

May 

117,500 

73,500 

191,000 

117.500 

73,500 

191,000 

113,300 

73,400 

186,700 

June 

124,200 

50,800 

175,000 

124,200 

50,800 

175,000 

119,700 

50,700 

170,400 

July 

125,400 

55,200 

180,600 

125,400 

55,200 

180,600 

121,100 

54,600 

175,700 

Aug 

126,700 

32,500 

159,200 

126,700 

32,500 

159,200 

122,300 

32,000 

154,300 

Sept. 

120,000 

23,800 

143,800 

120,000 

23,800 

143  800 

115,800 

23,500 

139,300 

Oct. 

113,400 

19,900 

133,300 

113,400 

19,900 

133,300 

109,500 

19,600 

123,100 

Nov. 

110,300 

27,500 

137,800 

110,300 

27.500 

137,800 

100,500 

27,100 

133,000 

Dec. 
Total  or 
average 

109,400 

44,500 

153,900 

109,400 

44,500 

153,900 

105,000 

70,000 

175,600 

113,000 

56,300 

109,300 

113,000 

59,500 

172,500 

109,100 

58,300 

167,400 

1917 

Jan. 

97,400 

0 

97,400 

97,400 

0 

97,400 

94,100 

0 

94,100 

Feb. 

101,900 

0 

101,900 

101,900 

11.600 

113,500 

98,500 

11,900 

110,400 

Mar. 

104,200 

53,500 

157,700 

104,200 

3,500 

107,700 

100,500 

87,500 

188,000 

April 

109,000 

101,000 

210,000 

109,000 

85,000 

194,600 

105,300 

73,500 

178,800 

May 

117,.500 

89,000 

206,500 

117,500 

89.000 

206,500 

113,300 

96,700 

210,000 

June 

124,200 

40,300 

164,500 

124,200 

40,300 

164,500 

119,700 

90,300 

210,000 

July 

125,400 

22,700 

148,100 

125,400 

22,700 

148,100 

121,100 

37,500 

158,000 

Aug. 

126,700 

20,400 

147,100 

126,700 

20,400 

147,100 

122,300 

19,800 

142,100 

Sept. 

120,000 

11,900 

131,900 

120,000 

11  900 

151,900 

115,800 

11,700 

127,500 

Oct. 

113,400 

5,400 

118,800 

113,400 

3,400 

118,800 

109,500 

5,200 

114,700 

Nov. 

110,300 

20,000 

130,300 

110,300 

20.000 

130,300 

106,500 

19,700 

126,200 

Dec. 

Total  or 
average 

109,400 

18,400 

127,800 

109,400 

18,400 

127,800 

105,600 

44,400 

150,000 

113,400 

32,000 

145,400 

113,400 

27,400 

140,800 

109,400 

41,700 

151,100 

1918 

Jan. 

97,400 

0 

97,400 

97,400 

0 

97,400 

94.100 

0 

94,100 

Feb. 

101,900 

0 

101,900 

101,900 

0 

101,900 

98,500 

0 

98,500 

Mar. 

104,200 

3.400 

107,000 

104,200 

3.400 

107,000 

100.500 

42,500 

143,000 

April 
May 

109,000 

91,100 

200,100 

109,000 

91,100 

200,100 

105,300 

21,400 

129,700 

117,500 

12,000 

129,.500 

117,500 

12,000 

129,500 

113,300 

0 

113,300 

June 

124,200 

0 

124,200 

124.200 

0 

124,200 

119,700 

0 

119,700 

July 

125,400 

5,100 

130,500 

12.').400 

5,100 

130.500 

121,100 

0 

121,100 

Aug. 

120,700 

11,200 

137,900 

12'),700 

11.200 

137,900 

122,300 

1,200 

12o,500 

Sept. 

120.000 

12,400 

132,400 

120,000 

12.400 

132,400 

115,800 

12,200 

128.000 

Oct. 

113,400 

28,900 

142.300 

113,400 

28.900 

142,300 

109,500 

28.500 

138,000 

Nov. 

110,300 

29,000 

13'J.300 

110,300 

29,000 

139,300 

106,500 

28,800 

135,300 

Dec. 
Total  or 
averego 

109,400 

3,600 

113,000 

109,400 

3,600 

113,000 

105,600 

28,800 

134,400 

113,400 

16,300 

129,700 

113,400 

16,300 

129,700 

109,400 

14,000 

123,400 

1919 

Jan. 

07.400 

0 

97,400 

97,400 

29.000 

126,400 

94,100 

0 

94,100 

Feb. 

101,900 

60,300 

171,200 

101.900 

99.600 

201,.500 

98.500 

83,800 

182.300 

Mar. 

104.200 

105,800 

210,000 

104.200 

95.200 

199,400 

100.500 

109,500 

210,000 

April 
May 

109,000 

101,000 

210,000 

109.000 

97.600 

206,000 

105,300 

40,400 

151.700 

117,500 

04,100 

181,000 

117,500 

64,100 

181,000 

113.300 

00,500 

173.800 

Juno 

124,200 

7,100 

131. .300 

124,200 

7,100 

131.300 

119,700 

7,400 

127.100 

July 

125,400 

14,800 

140,200 

125,400 

14,800 

140,200 

121.100 

14,700 

185,800 

Aug. 

120,700 

14,200 

140,900 

120,700 

14,200 

140,900 

122.300 

14,400 

136,700 

Sept. 

120.000 

4.000 

124,600 

120,000 

4,600 

124,600 

115,800 

4.600 

120,400 

Oct. 

113.400 

0.500 

119,iH)0 

113,41)0 

fi,.500 

119.900 

109,500 

6.500 

116,000 

Nov. 

110,300 

4,200 

114,500 

110,300 

4,200 

114,500 

106,500 

4,200 

•110,700 

Dec. 
ToUl  or 
average 

109.400 

0 

109,400 

109,400 

0 

109,400 

105,600 

0 

105,600 

113,400 

32,400 

145,800 

113,400 

36,000 

149,400 

109,400 

29,000 

138,400 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OP   FLOODS   BY   RESERVOIRS.  293 

RESERVOIR  ON  SACRAMENTO  RIVER. 

BOTH  WITH  AND  WITHOUT  FLOOD  CONTROL, 
la,  2a  and  4a. 

mary,  see  Table  5,  page  1 16.) 

Installed  capacity  of  power  plant  400,000  k.v.a.     P.P.  =  0.80. 


Operating  primarily  for  irrigation 

with  incidental  power  Generation 

SeasonaUrrigation  yield  4,276,000  acre-feet.    (Deficiency  in  supply  one  year  in  ten. 

no  deduction  for  downstream  prior  rights). 

Average  power  yield  in  kilowatts  (Load  factor=1.00) 

Coordinated  with  flood  control 

by  reservoir  operating  diagram 

Year  and 

Without  flood  control 

Maximam  controlled  flow 

month 

at  Red  Bluff  125,000  seo.-ft. 

Maximum  reservoir  space 

required  454,000  acre- 

feet 

Primary 

Secondary 

Total 

Primary 

Secondary 

Total 

0 

72,000 

72,000 

0 

160,900 

160,900 

1916 

0 
0 
0 
0 
0 

277,900 

277,900 

0 

278,500 

278,500 

Feb. 

280,000 

280,000 

0 

2.54,300 

254,300 

Mar. 

269,200 

269,''00 

0 

251,100 

251.100 

April 

May 

JUDG 

280,000 

280,000 

0 

280,000 

280,000 

280,000 

280,000 

0 

280.000 

280,000 

0 
0 
0 
0 
0 
0 

280,000 

280,000 

0 

280,000 

280,000 

July 

266,900 

266,900 

0 

266,900 

266,900 

Ajg. 
Sept. 

151,800 

151,800 

0 

151,800 

151,800 

47,000 

47,000 

0 

47,000 

47,000 

Oct. 

0 
0 

0 
0 

0 
0 

0 
0 

0 
0 

Nov. 
Dec. 

0 

183,300 

183,300 

0 

187,200 

187,200 

Total  or 
average 

0 
0 
0 
0 

0 

0 

0 

0 

0 

1917 

Jan. 

17.900 

0 

17,900 

0 
0 

0 
17,900 

0 

17,900 

Feb. 
Mar. 

234,400 

234,400 

0 

234.400 

234,400 

April 
May 

0 
0 
0 
0 
0 
0 
0 
0 

280,000 

280,000 

0 

280,000 

280,000 

280,000 

280,000 

0 

280.000 

280,000 

June 

280,000 

280,000 

0 

280,000 

280,000 

July 

263,400 

263,400 

0 

263,400 

263,400 

Aug. 

147,600 

147,600 

0 

147,600 

147,600 

Sept. 

44,600 

44,600 

0 

44,600 

44,600 

Get. 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

Dec. 

0 

129,700 

129,700 

0 

129,700 

129,700 

Total  or 
average 

0 
0 
0 
0 
0 
0 
0 
0 
n 

0 

0 

0 

0 

0 

1918 

Jan. 

0 
16,900 

0 
16,900 

0 

0 

0 

16,900 

0 

16,900 

Feb. 
Mar. 

92,500 

92,500 

0 

92,500 

92.500 

April 

280,000 

280,000 

0 

280,000 

280,000 

May 

280,000 

280.000 

0 

280,000 

280,000 

June 

280,000 

280,000 

0 

280,000 

280,000 

July 

197,400 

197,400 

0 

197,400 

197,400 

Aug. 

oooc 

1 

0 
0 

0 
0 

0 
0 

0 
0 

0 
0 

Sept. 
Oct. 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

Dec. 

0 

96,400 

96,400 

0 

96,400 

96,400 

Total  or 
average 

0 
0 
0 
0 
0 

1919 

0 

0 

0 

0 

0 

Jan. 

0 
143.100 

0 
143,100 

0 
0 

0 

209,800 

0 
209,800 

Feb. 
Mar. 

274,300 

274,300 

0 

258,600 

258,000 

April 

280,000 

280,000 

0 

280,000 

280,000 

May 

0 
0 
0 
0 
0 
0 
0 

280.000 

280,000 

0 

280,000 

280,000 

June 

280,000 

280,000 

0 

280,000 

280,000 

July 

235,.500 

235..500 

0 

235.500 

235,500 

Aug. 

124,600 

124,600 

0 

124,600 

124,600 

Sept. 

35,600 

35,600 

0 

35,600 

35,600 

Oct. 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

Dec. 

0 

138,500 

138,500 

0 

142,900 

142,900 

Total  or 
average 

294 


WATER  RESOURCES   OP   CALIFORNIA. 


Height  of  dam  420  feet. 


TABLE  5a  (Continued).     KENNETT 

SUMMARY  OF  POWER  YIELD  BY  MONTHS 

Summary  of  Tables 

(For  corresponding  yearly  sum 
Capacity  of  reservoir  2,940,000  acre-feet. 


Operating  primarily  for  power  generation  with  incidental  irrigat 

on 

Average  power  yielc 

in  kilowatt 

s  (Load  fact( 

)r=0.75) 

Coordinated  with  flood  control 

With  flood  control,  holding 

Year  and 

by  reservoir  operating  diagram 

maximum  reservoir  space 

month 

t\r:,l,„„,  <!„„,)  „„„♦,„! 

Maximum  controlled  flow 

required  (454,000  ac.-ft.)  in 

»  HI 

at  Red  Bluff  125,000  sec.-ft 

reserve  throughout  flood  season 

Maximum  reservoir  space 

Maximum  controlled  flow 

required  454,000  acre-feet 

at  Red  Bluff  125,000  sec.-ft. 

'Primary 

Secondary 

Total 

•Primary 

Secondary 

Total 

•Primary 

Secondary 

Total 

1920 

Jan. 

07,400 

0 

97.400 

97,400 

0 

97,400 

94,100 

0 

94,100 

Feb. 

98,400 

0 

98,400 

98,400 

0 

98,400 

95,100 

0 

95,100 

Mar. 

104,200 

0 

104,200 

104,200 

0 

104,200 

100,500 

0 

100,500 

April 

109,000 

0 

109,000 

109,000 

0 

109,000 

105,300 

0 

105,300 

May 

117,500 

0 

117,500 

117,500 

0 

117,500 

113,300 

0 

113,300 

June 

124,200 

0 

124,200 

124,200 

0 

124,200 

119,700 

0 

119,700 

July 

125,400 

0 

125,400 

125,400 

0 

125,400 

121,100 

0 

121,100 

Aug. 

126,700 

0 

126,700 

126,700 

0 

126,700 

122,300 

0 

122,300 

Sept. 

120,000 

0 

120,000 

120,000 

0 

120,000 

115,800 

0 

115,800 

Oct. 

113,400 

0 

113,400 

113,400 

0 

113.400 

109,500 

0 

109,500 

Nov. 

110,300 

10.400 

120,700 

110,300 

10.400 

120,700 

106,500 

0 

106,500 

Dec. 

109,400 

100,600 

210,000 

109,400 

100.600 

210,000 

105,600 

77,300 

182,900 

Total  or 
average 

113,000 

9,400 

122,400 

113,000 

9,400 

122,400 

109,100 

6,500 

115,600 

1921 

Jan. 

97,400 

112,600 

210,000 

97,400 

112,600 

210,000 

94,100 

115,900 

210,000 

Feb. 

101,900 

108,100 

210,000 

101,900 

108,100 

210,000 

98,500 

111,500 

210,000 

Mar. 

104,200 

105,800 

210,000 

104,200 

100,900 

205,100 

100,500 

109,500 

210,000 

April 

109.000 

99,000 

208,000 

109,000 

71,900 

180,900 

105,300 

24,400 

129,700 

May 

117,500 

83,200 

200,700 

117,500 

83,200 

200,700 

113,300 

51,100 

164,400 

June 

124,200 

34,600 

158,800 

124,200 

34,600 

158,800 

119,700 

34,700 

154,400 

July 

125,400 

15,200 

140,600 

125,400 

15,200 

140,600 

121,100 

15,100 

136,200 

Aug. 

126,700 

11,200 

137,900 

126,700 

11,200 

137.900 

122,300 

11,600 

133,900 

Sept. 

120,000 

7.800 

127,800 

120,000 

7,800 

127,800 

115,800 

7,500 

123,300 

Oct. 

113,400 

0 

113,400 

113,400 

0 

113,400 

109,500 

3,600 

113,100 

Nov. 

110,300 

16,300 

126,600 

110,300 

16,300 

126,600 

106,500 

11,900 

118,400 

Dec. 
Total  or 
average 

109,400 

28.900 

138,300 

109,400 

28,900 

138,300 

105,600 

47,200 

152,800 

113.400 

51,600 

165,000 

113,400 

48,900 

162,300 

109,400 

45,100 

164,500 

1922 

Jan. 

97,400 

0 

97,400 

97,400 

0 

97,400 

94,100 

0 

94,100 

Feb. 

101,900 

0 

101,900 

101,900 

19,900 

121,800 

98,500 

28,000 

126,500 

Mar. 

1Q1,200 

60,100 

164,300 

104,200 

7,300 

111,500 

100,500 

97,300 

197,800 

April 

109,000 

93,600 

202,600 

109,000 

93,600 

202,600 

105,300 

24,400 

129,700 

May 

117,500 

88,300 

205,800 

117,500 

88,300 

205,800 

113,300 

74,900 

188,200 

Jane 

124,200 

35,000 

159,200 

124,200 

35,000 

159,200 

119,700 

50,300 

170,000 

July 

125,400 

7,900 

133,300 

125,400 

7,900 

133,300 

121,100 

7,900 

129,000 

Aug. 

120,700 

7,100 

133,800 

126,700 

7,100 

133,800 

122,300 

7,400 

129,700 

Sept. 

120,000 

1,700 

121,700 

120,000 

1,700 

121,700 

115,800 

1,700 

117,500 

Oct. 

113,400 

8,600 

122,000 

113,400 

8  000 

122,000 

109,500 

8,500 

118,000 

Nov. 

110,300 

28,300 

138,600 

110,300 

28,300 

138,600 

106,500 

27,900 

134,400 

Dec. 
Total  or 

109,400 

55,100 

164,500 

109.400 

55,100 

164,500 

105,600 

76.900 

182,500 

average 

113.400 

32.300 

145,700 

113.400 

29,400 

142,800 

109,400 

33.900 

143,300 

1923 

Jan. 

97,400 

52,400 

149,800 

97,400 

52,400 

149,800 

94,100 

0 

94,100 

Feb. 

101.900 

0 

101,900 

101.000 

0 

101.900 

98,500 

0 

98,600 

Mar. 

101.200 

0 

104,200 

104.200 

0 

iaj,200 

100,500 

9.000 

109,500 

April 
May 

100.000 

0 

109.000 

109.000 

0 

109,000 

105,300 

20.600 

125,900 

117.500 

1.300 

118,800 

117,500 

1,300 

118,800 

113,300 

0 

113,300 

June 

124.200 

0 

124,200 

124,200 

0 

124,200 

119,700 

0 

119,700 

July 

126.400 

0 

125,400 

125.400 

0 

125.400 

121,100 

0 

121,100 

Aug. 

126.700 

0 

126,700 

126.700 

0 

126,700 

122,300 

0 

122,300 

Sept. 

120.000 

0 

120,000 

120.000 

0 

120,000 

115,800 

0 

115,800 

Oct. 

113.400 

0 

113,400 

113.400 

0 

11.3,400 

109,500 

0 

109,500 

Nov. 

110.300 

0 

110,300 

1 10.300 

0 

110,300 

106.500 

0 

106,500 

Dec. 
Total  or 

109.400 

0 

109,400 

109.400 

0 

109,400 

105.600 

0 

105,000 

average 

113,400 

4.600 

118.000 

113.400 

4.600 

118.000 

109,400 

2.500 

111,900 

*TotaI  primtry  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THK    CONTKOL   OF   FLOODS   BY    RESERVOIRS. 


295 


RESERVOIR  ON  SACRAMENTO  RIVER. 

BOTH  WITH  AND  WITHOUT  FLOOD  CONTROL, 
la,  2a  and  4a. 

mary,  see  Table  5,  page  1 16.) 

Installed  capacity  of  power  plant  400,000  k.v.a. 


P.P.  =0.80. 


Operating  primarily  for  Irrigation  with  Incidental  power  generation 

Seasonal  irrigition  yield  4,276,000  aore-feet.    (Deficiency  in  supply  one  year  in 

ten, 

no  deduction  for  downstream  prior  rights). 

Average  power  yield  in  kilowatts  (Load  factor=1.00) 

Coordinated  with  flood  control 

by  reservoir  operating  diagram 

Year  and 

Without  flood  control 

Maximum  controlled  flow 
at  Red  Bluff  125,000  sec.-ft. 

month 

Maximum  reservoir  space 

required  454,000  acre- 

feet 

Primary 

Secondary 

Total 

Primary 

Secondary 

Total 

1920 

0 

0 

0 

0 

0 

0 

Jan. 

0 

0 

0 

0 

0 

0 

Feb. 

0 

14,500 

14,500 

0 

14,500 

14,500 

Mar. 

0 

80,100 

80,100 

0 

80,100 

80,100 

April 

0 

243,300 

243,300 

0 

243,300 

243,300 

May 

0 

233,300 

233,300 

0 

233,300 

233,300 

June 

0 

69,100 

69,100 

0 

09,100 

69,100 

July 

0 

0 

0 

0 

0 

0 

Aug. 

0 

0 

0 

0 

0 

0 

Sept. 

0 

0 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 

0 

53,400 

53,400 

0 

53,400 

53,400 

average 
1921 

0 

07,700 

67,700 

0 

134,700 

134,700 

Jan. 

0 

280,000 

280,000 

0 

280,000 

280,000 

Feb. 

0 

280,000 

280,000 

0 

280,000 

280,000 

Mar. 

0 

236,500 

236,500 

0 

190,600 

190,600 

April 

0 

280,000 

280,000 

0 

280,000 

280,000 

May 

0 

280,000 

280,000 

0 

280,000 

280.000 

June 

0 

280,000 

280,000 

0 

280,000 

280,000 

July 

0 

249,200 

249,200 

0 

249,200 

249.200 

Aug. 

0 

136,300 

136,300 

0 

136,300 

136,300 

Sept. 

0 

40,100 

40,100 

0 

40,100 

40,100 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 

0 

176,800 

176,800 

0 

178,700 

178.700 

average 
1922 

0 

0 

0 

0 

0 

0 

Jan. 

0 

0 

0 

0 

0 

0 

Feb. 

0 

17,300 

17,300 

0 

17,300 

17,300 

Mar. 

0 

95,600 

95,600 

0 

95,600 

95,600 

April 

0 

280,000 

280,000 

0 

280,000 

280,000 

May 

0 

280,000 

280,000 

0 

280,000 

280,000 

June 

0 

280,000 

280,000 

0 

280,000 

280,000 

July 

0 

255,400 

255,400 

0 

255,400 

255,400 

Aug. 

0 

140,400 

lr0,400 

0 

140,400 

140,400 

Sept. 

0 

41,800 

41,800 

0 

41,800 

41,800 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 

0 

116,700 

116,700 

0 

116,700 

116,700 

average 
1923 

0 

0 

0 

0 

0 

0 

Jan. 

0 

0 

n 

0 

0 

0 

Feb. 

0 

16,900 

16,900 

0 

16,900 

16,900 

Mar. 

0 

90,700 

90,700 

0 

90,700 

90,700 

April 
May 

0 

278,600 

278,600 

0 

278,600 

278,000 

0 

280,000 

280,000 

0 

280,000 

280,000 

June 

0 

264,300 

264,300 

0 

264,300 

264,300 

July 

0 

154,200 

154,200 

0 

154,200 

154,200 

Aug. 

0 

0 

0 

0 

0 

0 

Sept. 

0 

0 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 

0 

91,100 

91,100 

0 

91,100 

91,100 

average 

29G 


WATER  RESOURCES  OP   CALIFORNIA. 


Height  of  dam  420  feet. 


TABLE  5a  (Concluded).     KENNETT 

SUMMARY  OF  POWER  YIELD  BY  MONTHS 

Summary  of  Tables 

(For  corresponding  yearly  sum 
Capacity  of  reservoir  2,940,000  acre-feet. 


Operating  primarily  for  power  generation  with  incidental  irrigat 

.\verage  power  jield  in  kilowatts  (Load  factor=0.75; 

on 

Year  and 
month 

Without  flood  control 

Coordinated  with  flood  control             With  flood  control,  holding 

by  reservoir  operating  diagram              maximum  reservoir  space 

Maximum  controlled  flow                  required  (454,000  ac.-ft.)  in 

at  Red  Bluff  125,000  sec.-f t.        :     resene  throughout  flood  season 

Maximum  reservoir  space                  Maximum  controlled  flow 

required  454,000  acre-feet         1       at  Red  Bluff  125,000  sec.-ft. 

*Priinary 

Secondary 

Total 

•Primary 

Secondary 

Total 

'Primary 

Secondary  i      Total 

1924 

Jan. 
Feb. 
Mar. 
April 
May 
June 
July 
Aug 
Sept. 
Oct.. 
Nov. 
Dec. 
Total  or 
average 

1925 
Jan. 
Feb. 
Mar. 
April 
May 
June 
July 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
Total  or 
average 

Average 

for 

30-year 

period. 

1896-1926 

97.400 
98.400 
104,200 
109,000 
117,500 
124,200 
125,400 
126,700 
120,000 
113,400 
110,300 
109,400 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

97,400 
98,400 
104,200 
109,000 
117.500 
124,200 
125.400 
126,700 
120,000 
113,400 
110,300 
109,400 

97.400 
98.400 
104,200 
109,000 
117,500 
124,200 
125,400 
126,700 
120,000 
113.400 
110,300 
109,400 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

97,400 
98,400 
104,200 
109.000 
117,500 
124,200 
125,400 
126,700 
120,000 
113,400 
110,300 
109,400 

94,100 
95,100 
100,500 
105,300 
113,300 
119,700 
121,100 
122,300 
115,800 
109,500 
106,500 
105,600 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

94,100 
95.100 
100,500 
105,300 
113,300 
1)9,700 
121,100 
122,300 
115.800 
109,500 
106,500 
105,600 

113,000 

97.400 
101,900 
104,200 
109,000 
117,500 
124,200 
125,400 
126,700 
120,000 
113,400 
110,300 
109,400 

0 

0 

0 

0 

53,800 

70,800 

17,500 

0 

0 

0 

0 

2,500 

0 

113.000 

97,400 
101,900 
104,200 
162,800 
188,300 
141,700 
125,400 
126,700 
120,000 
113,400 
112,800 
109.400 

113,000 

97.400 
101.900 
104,200 
109,000 
117,500 
124,200 
125,400 
126,700 
120,000 
113,400 
110,300 
109,400 

0 

0 

0 

0 

53,800 

70,800 

17,500 

0 

0 

0 

0 

2.500 

0 

113.000 

97.400 
101.900 
104,200 
162,800 
188,300 
141,700 
125.400 
126.700 
120,000 
113,400 
112,800 
109.400 

109,100 

94,100 
98,500 
100,500 
105,300 
113,300 
119,700 
121,100 
122,300 
115,800 
109,500 
106,500 
105,600 

0 

0 

0 

21,900 

66,500 

96,700 

42,900 

0 

0 

0 

0 

2,100 

19,600 

109,100 

94,100 
98,500 
122.400 
171,800 
210,000 
162,600 
121,100 
122,300 
115,800 
109.500 
108,600 
125,200 

113.400 
113,400 

12.100 
44,800 

125.500 
158,200 

113.400 
113,400 

12,100 
43,400 

125,500 
158,800 

109,400 
109,400 

20,900 
47.300 

130,300 
156,700 

•Total  primary  power  production  in  February  of  leap  years  taken  the  same  as  in  other  years. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


297 


RESERVOIR  ON  SACRAMENTO  RIVER. 

BOTH  WITH  AND  WITHOUT  FLOOD  CONTROL. 

la,  2a  and  4a. 

mary,  see  Table  5,  page  1 16.) 

Installed  capacity  of  power  plant  400,000  k.v.a.     P.P.  =  0.80. 


Operating  primarily  for  irrigation  with  incidental  power  generation 

Seasonalirrigation  yield  4,276,000  acre-feet.    (Deficiency  in  supply  one  year  in 
no  deduction  for  downstream  prior  rights). 
Average  power  yield  in  kilowatts  (Load  factor=1.00) 

ten. 

Without  flood  control 

Coordinated  with  flood  control 

by  reservoir  operating  diagram 

Maximum  controlled  flow 

at  Red  Bluff  125,000  sec.-ft. 

Maximum  reservoir  space 

required  454,000  acre-feet 

Year  and 
month 

Primary 

Secondary 

Total 

Primary 

Secondary 

Total 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 

0 

13,400 

70,700 

191,400 

30,000 

0 

0 

0 

0 

0 

0 

0 
0 

13,400 

70,700 

191,400 

30,000 

0 

0 

0 

0 

0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 

0 

13,400 

70,700 

191,400 

30,000 

0 

0 

0 

0 

0 

0 

0 

0 

13,400 

70,700 

191,400 

30,000 

0 

0 

0 

0 

0 

0 

1924 

Jan. 

Feb. 

Mar 

April 

May 

June 

July 

Aug. 

Sept. 

Oct. 

Nov. 

Dec. 
Total  or 
average 

1925 

Jan. 

Feb. 

Mar. 

April 

May 

June 

July 

Aug. 

Sept. 

Oct. 

Nov. 

Dec. 
Total  or 
average 

Average 

for 

30-year 

period, 

1896-1926 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

25,600 

0 

0 

143,800 

277,500 

280,000 

280,000 

280,000 

234,100 

122,400 

0 

0 

0 

25,600 

0 

0 

143,800 

277,500 

280,000 

280,000 

280,000 

234,100 

122,400 

0 

0 

0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

25,600 

0 

49,900 

98,800 

256,900 

280,000 

280,000 

280,000 

234,100 

122,400 

0 

0 

0 

25,600 

0 

49,900 

98,800 

256,900 

280,000 

280,000 

280,000 

234,100 

122,400 

0 

0 

0 

0 
0 

135,500 
145,300 

135,500 
145,300 

0 
0 

133,900 
145,600 

133,900 
145,600 

298  WATER  RESOURCES  OF   CALIFORNIA. 

ASSUMPTIONS  EMPLOYED  IN  COMPUTING  WATER  AND  POWER  YIELD 
OF  PARDEE  RESERVOIR  ON   MOKELUMNE  RIVER  ON   DAILY  BASIS. 

1.  Water  supply  at  dam  site  is  the  same  as  that  measured  at  the 
Clements  "ragin?  station  of  the  United  States  Geological  Survey  and 
published,  or  in  preparation  for  publication,  as  mean  daily  discharges 
in  the  Water  Supply  Papers.  A  deduction  of  140.000  acre-feet  per 
year  is  made  for  downstream  prior  rights  in  estimating  the  reservoir 
yield  for  domestic  purposes.  This  water  is  utilized  in  the  generation  of 
power. 

2.  The  reservoir  is  full  on  July  1,  1904,  the  opening  date  of  computa- 
tions. The  run-off  index  for  the  sea.son  1903-1904  is  108.  The  reser- 
voir fills  in  1925  with  a  run-off  index  of  92. 

3.  The  net  evaporation  from  the  reservoir  surface  equals  2.67  feet 
depth  per  annum  divided  among  the  months  as  follows:  (Taken  from 
Annual  Report  of  East  Bay  Municipal  Utility  District  for  1925,  p.  42.) 

Evaporation   and    Rainfall   at    Lancha    Plana    Reservoir. 
Quantities  in  inches  depth. 

Month  Evai'oration  Rainfall  Net  loss 

October 3.90  1.18  2.72 

November 1.70  2.G4  -  .94 

December .90  3.72  -2.82 

January    .81  4.39  -3.58 

February    1.26  3.4S  -2.22 

March 2.37  4.G6  -2.29 

April    4.04  2.06  1.98 

May    0.81  1.15  5.66 

June   8.00  .29  7.71 

July 10.19  .00  10.19 

August    9.07  .00  9.07 

September    6.95  .43  6.52 

Year    50.00  24.00  32.00 

4.  The  municipal  sup])ly  is  drawn  from  the  reservoir  iit  a  uniformly 
constant  rate  of  200,000,000  gallons  i)er  day. 

5.  Power  is  generated  in  a  plant  at  the  base  of  the  dam  with  water 
passing  by  the  dam  for  downstream  prior  rights,  reservoir  spill,  and 
some  water  drawn  from  reservoir  in  addition  to  the  municipal  draft  in 
accord  with  schedule  of  operation  dated  August  ;}.  1927,  submitted  by 
East  Bay  IMuuicipal  Utility  Di.strict.  IMaximum  flow  through  turbines 
750  second-feet.  Power  is  not  generated  from  the  municipal  draft 
from  the  reservoir. 

6.  Capacity  of  power  plant  is  15,000  kilowatts. 

7.  Overall  efficiency  of  ])ower  plant  i.s  72.6  per  cent  for  all  reservoir 
levels. 

8.  Load  factor  on  power  plant  1.00. 

9.  The  elevation  of  Avatei-  in  the  tail  race  is  242.5  feet,  constant  for 
all  discharges. 


300 


WATER  RESOURCES  OF   CALIFORNIA. 

TABLE  6a.     PARDEE  RESERVOIR 


WATER  AND  POWER  YIELD  BOTH  WITH  AND  WITHOUT 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


Without  flood  control 

Power 

Year  and 
month 

Run-off 

at 
Clements 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

draft 
through 
turbines 
including 

water 
passed 
for  prior 
rights  in 
acre-feet 

Evapora- 
tion in 
acre-feet 

Waste 
over 

spillway 
in 

acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

1905 

Jan. 

26,320 

145,860 

19,030 

10,500 

+   610 

0 

0 

282 

2.960 

Feb. 

47,370 

143,260 

17,190 

22,500 

+    380 

0 

0 

285 

7.100 

Mar. 

86,700 

151,320 

19,030 

46,120 

+   430 

0 

0 

290 

13,370 

April 

116,600 

173,300 

18,410 

44,630 

—   370 

4,490 

0 

311 

14,380 

May 

150.600 

222,000 

19,030 

46,120 

—1,070 

90,380 

0 

325 

15,000 

June 

99,070 

222,000 

18,410 

40,910 

-1,460 

41.010 

0 

325 

13,700 

July 

11.560 

219,280 

19,030 

11,560 

—1,9,30 

0 

0 

319 

3,680 

Aug. 

7,870 

198,320 

19,030 

7,870 

— 1,.550 

0 

0 

308 

2,430 

Sept. 

8,270 

177,740 

18,410 

8,270 

—    990 

0 

0 

297 

2,540 

Oct. 

7.010 

158.310 

19,030 

3,000 

—   390 

0 

0 

287 

860 

Nov. 

4,730 

142,930 

18,410 

0 

-1-    120 

0 

U 

0 

Dec. 
Total  or 
average 

5,960 

129,370 

19,030 

0 

+   360 

0 

0 

0 

578,060 

224,040 

241,480 

—5,860 

135,880 

0 

303 

6.320 

1906 

Jan. 

61,200 

116,660 

19,030 

0 

+    420 

0 

0 

0 

Feb. 

44,900 

159,250 

17,190 

41,650 

-1-    320 

0 

0 

283 

13,0,50 

Mar. 

155,000 

145,630 

19.030 

46,120 

+   370 

13,850 

0 

296 

13.680 

April 

175,000 

222,000 

18.410 

44,630 

—    370 

111,590 

0 

325 

15,000 

May 

289,000 

222,000 

19,030 

46,120 

—1,070 

222.780 

0 

325 

15,000 

June 

358.000 

222,000 

18,410 

44,630 

-1.460 

293.500 

0 

325 

15,000 

July 

218.000 

222,000 

19,030 

44,010 

—1,930 

1,52,.560 

0 

325 

14,500 

Aug. 

21.900 

221.870 

19  030 

31,900 

—1.720 

0 

0 

317 

10.130 

tkpt. 

12,000 

191.120 

18.410 

11,600 

—  1.110 

0 

0 

305 

3,650 

Oct. 

11,700 

172.000 

19.030 

6,500 

—    410 

0 

0 

296 

1.920 

Nov. 

14,800 

157.760 

18,410 

3,000 

+    140 

0 

0 

289 

900 

Dec. 
Total  or 
average 

53,900 

151,290 

19,030 

5,000 

+   420 

0 

0 

292 

1.470 

1,415,400 

224,010 

325,760 

—6,400 

794.280 

0 

307 

8,650 

1907 

Jan. 

70,100 

181, ,580 

19,030 

46,120 

+    630 

0 

(1 

304 

14,010 

Feb. 

154,000 

187,160 

17,190 

41,6,50 

+    420 

60.740 

0 

323 

14,930 

Mar. 

300,000 

222,000 

19.030 

46.120 

-t-    430 

235,280 

0 

325 

15,000 

April 
Nfay 

264,000 

222,000 

18.410 

44,630 

—    370 

200,590 

0 

325 

15,000 

259,000 

222,001) 

19,030 

46,120 

—  1,070 

192,780 

0 

325 

15,000 

June 

281,000 

222,000 

18,410 

44,630 

—1.460 

216,500 

0 

325 

15,000 

July 

205,000 

222,000 

19,030 

40,120 

—1.930 

137,920 

0 

325 

15,000 

Aug. 

43,200 

222,000 

19,030 

31,290 

—1,720 

2.700 

0 

323 

10,130 

Sept. 

15,300 

210,400 

18,410 

30,500 

—1,2,30 

0 

0 

311 

9,810 

Oct. 

17,000 

175,620 

19,030 

9,500 

—   490 

0 

0 

299 

2.840 

Nov. 

13,900 

163,600 

18,410 

9,000 

+    160 

0 

0 

290 

2.710 

Dec. 
Total  or 
average 

20.200 

150.250 

19,030 

3.000 

+   480 

0 

0 

286 

860 

1.042.700 

224,040 

398.680 

—6,150 

1.046.510 

0 

313 

10.820 

1908 

Jan 

33.000 

148,900 

19,030 

12,500 

+    610 

0 

0 

286 

3,580 

Feb. 

22.000 

150.980 

17.800 

28,500 

+   400 

0 

0 

279 

8.510 

Mar. 

50,200 

127.689 

19,030 

33.470 

+    430 

0 

0 

302 

10,090 

April 
May 

103.000 

125.810 

18.410 

44,630 

-    370 

0 

0 

277 

12.780 

117,000 

105.400 

19,030 

4(i,120 

—1,070 

0 

0 

310 

14,300 

Juno 

75.000 

216.180 

18,410 

40,220 

—1,460 

10,770 

0 

325 

13..50O 

July 

14,100 

220,320 

19,030 

14,100 

—  1,930 

0 

0 

319 

4,,iOO 

Aug. 

(!,400 

19!),360 

19,030 

6,400 

—1,550 

0 

0 

30D 

1,980 

Sept. 

8,030 

178.780 

18,410 

8,030 

-    990 

0 

0 

297 

2.470 

Got. 

8,7.30 

1.59.380 

19.030 

3.000 

—   390 

0 

0 

288 

860 

Nov. 

7„380 

145.090 

18,410 

0 

-f-   130 

0 

0 

0 

Dec. 
Total  or 
average 

9.900 

134,790 

19.030 

0 

-t-    370 

0 

0 

0 

455,340 

224,650 

236,970 

—5,820 

10.770 

0 

299 

6,020 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


301 


ON  MOKELUMNE  RIVER. 

FLOOD  CONTROL  BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  6,  page  124.) 

Yield  in  municipal  supply  200  million  gallons  daily. 
Installed  capacity  of  power  plant  15,000  k.w. 


Coordinated  with  flood  control  by  reservoir  operatinq  diaqram 

Maximum  controlled  fiow  at  Clements — rain- 

vater  floods,  5,300  sec.-ft.:  snow-water  floods,  7,100  sec.-ft. 

Maxim 

um  reservoir  space  required— rain-water  floods,  92,000  ac.-ft.;  snow-water  floods,  13,000  ac.-ft. 

Power 

Stage  of 

draft 
through 

Release 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

Average 
power 

Average 

Year  and 

reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

turbines 
including 
water 
passed 
for  prior 
rights  in 

Evapora- 
tion in 
acre-feet 

through 

flood 

control 

outlets  in 

acre-feet 

in_ 

municipal 

supply 

in 
acre-feet 

head 

through 

period 

of 

operation 

m  feet 

power 
yield  in 
kilowatts 

(Load 
factor= 

1.00) 

month 

acre-feet 

1905 

145,860 

19,030 

10,500 

+    610 

0 

0 

0 

282 

2,960 

Jan. 

143.260 

17,100 

22,500 

+    380 

0 

0 

0 

285 

7,100 

Feb. 

151.320 

19,0.30 

46,120 

+    430 

0 

0 

0 

290 

13,370 

Mar. 

173,300 

18,410 

44,630 

—    370 

0 

4,490 

0 

311 

14,380 

April 

222,000 

19,030 

46,200 

—1,070 

73,570 

21,890 

0 

324 

15,000 

May 

216,840 

18,410 

40,510 

—1,460 

38,270 

0 

0 

323 

13,540 

June 

217,260 

19,030 

11,560 

—1,930 

0 

0 

0 

318 

3,680 

July 

196,300 

19,030 

7,870 

—1,550 

0 

0 

0 

307 

2,420 

Aug. 

175,720 

18,410 

8,270 

—    990 

0 

0 

0 

296 

2,530 

Sept. 

156,320 

19,030 

3,000 

—   390 

0 

0 

0 

285 

860 

Oct. 

140,910 

18,410 

0 

+    120 

0 

0 

0 

0 

Nov. 

127,350 

19,030 

0 

+    360 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

241,160 

-5,860 

111,840 

26,380 

0 

302 

6,300 

1906 

114,640 

19,030 

0 

-1-    420 

0 

0 

0 

0 

Jan. 

157,2.30 

17,190 

41,650 

+    320 

0 

0 

0 

282 

13,020 

Feb. 

143,610 

19,030 

44,580 

+    370 

63,140 

0 

0 

289 

12.880 

Mar. 

172.230 

18,410 

43,760 

—   370 

26,850 

35,840 

0 

314 

14,220 

April 

222,000 

19,030 

46,430 

—1,070 

137,.510 

96,860 

0 

323 

15,000 

May 

210,100 

18,410 

45,110 

—1,460 

285,980 

0 

0 

o22 

15,000 

June 

217,140 

19,030 

44,620 

—1,930 

48,070 

99,620 

0 

325 

14,500 

July 

221,870 

19,030 

31,900 

-1,720 

0 

0 

0 

317 

10,130 

Aug. 

191,120 

18,410 

11,600 

—1,110 

0 

0 

0 

305 

3,650 

Sept. 

172,000 

19,030 

6,500 

-    410 

0 

0 

0 

296 

1,920 

Oct. 

157.760 

18,410 

3,000 

+    140 

0 

0 

0 

289 

900 

Nov. 

151,290 

.    19,030 

11.310 

+   420 

9,600 

0 

0 

292 

3,370 

Dec. 
Total  or 
average 

224,040 

330,460 

—6,400 

571,150 

232,320 

0 

305 

8,680 

165,670 

19.030 

49,580 

+    630 

33,160 

0 

0 

283 

14,050 

1907 

Jan. 

134,630 

17,190 

49,240 

+   420 

91,070 

0 

0 

275 

16,000 

Feb. 

131,550 

19,030 

51,000 

+    430 

149,290 

0 

0 

294 

14,950 

Mar. 

212,660 

18,410 

45,470 

—   370 

128,450 

61,960 

0 

319 

15.000 

April 

222,000 

19,030 

46,120 

—1,070 

11,670 

.    181,110 

0 

325 

15,000 

May 

222,000 

18,410 

44,630 

—1,460 

107,620 

108,880 

0 

325 

15,000 

June 

222,000 

19,030 

46.120 

—1,930 

0 

137,920 

0 

325 

15.000 

July 

222,000 

19,030 

31,290 

■   —1,720 

0 

2,700 

0 

323 

10,130 

Aug. 

210,460 

18,410 

30.500 

—1,230 

0 

0 

0 

311 

9,810 

Sept. 

175,620 

19,030 

9,600 

—   490 

n 

0 

0 

299 

2,840 

Oct. 

163,600 

18,410 

9,000 

4-    160 

0 

0 

0 

290 

2,710 

Nov. 

150,250 

19,030 

3,000 

-1-    480 

0 

0 

0 

286 

860 

Dec. 
Total  or 
average 

224,040 

415,450 

—6,1.50 

521,260 

492,570 

0 

305 

10,820 

148,900 

19,030 

12,,500 

+    610 

0 

0 

0 

286 

3,580 

1908 

Jan. 

150,980 

17,800 

28,500 

4-   400 

0 

0 

0 

279 

8,510 

Feb. 

127,680 

19,030 

33,470 

+   430 

0 

0 

0 

302 

10,090 

Mar. 

125,810 

18,410 

44,630 

—   370 

0 

0 

0 

277 

12,780 

April 

165,400 

19,030 

46,120 

— 1;070 

0 

0 

0 

310 

14,300 

May 

216,180 

18,410 

40,220 

—1,460 

0 

10,770 

0 

325 

13,500 

June 

220,320 

19,030 

14,100 

—1,930 

0 

0 

0 

319 

4.500 

July 

199,360 

19.030 

0,400 

-1,5.50 

0 

0 

0 

309 

1,980 

Aug. 

178,780 

18,410 

8,030 

—   990 

U 

0 

0 

297 

2,470 

Sept. 

159,380 

19.030 

3.000 

—    390 

0 

0 

0 

288 

860 

Oct. 

145,690 

18,410 

0 

-f-    1.30 

0 

0 

0 

0 

Nov. 

134,790 

19,030 

0 

+    370 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,650 

236,970 

-5,820 

0 

10,770 

0 

299 

6,020 

302 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  6a  (Continued).     PARDEE  RESER 

WATER  AND  POWER  YIELD  BOTH  WITH  AND  WITHOUT 

Monthly  Summary  of  Computa 

(For  correspxinding  yearly  sum 


Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


Run-off 

at 
Clements 

Without  flood  control 

Year  and 
month 

Stage  of 
reservoir 

Municipal 

Power 

draft 

through 

turbines 

Evapora- 
tion in 
acre-feet 

Waste 

Deficiency 
in 

Average 
power 
head 

Average 
power 

yield  in 

kilowatts 
(Load 

factor^ 
1.00) 

in 

acre-feet 

at 
beginning 

of 
month  in 
acre-feet 

draft 

in 

acre-feet 

including 

water 

passed 

for  prior 

rights  in 

over 
spillway 

in 
acre-feet 

municipal 
supply 

in 
acre-feet 

through 

period 

of 

operation 
in  feet 

acre-feet 

1909 

Jan. 

179,000 

126,030 

19,030 

17.330 

+    440 

47.110 

0 

300 

5,590 

Feb. 

126,000 

222,000 

17,190 

41,650 

+    420 

67,580 

0 

325 

15,000 

Mar. 

103,000 

222,000 

19,030 

46,120 

+    430 

38,280 

0 

325 

15.000 

April 

167.000 

222,000 

18,410 

44,630 

—    370 

103,590 

0 

325 

15,000 

May 

228,000 

222,000 

19,030 

46,120 

—1,070 

iei,780 

0 

325 

15,000 

June 

256,000 

222,000 

18,410 

44,630 

—1,460 

191,500 

0 

325 

15,000 

July 

50,700 

222,000 

19,030 

31,080 

—  1,930 

8,950 

0 

324 

10,080 

Aug. 

7,070 

211,710 

19,030 

17,070 

—  1,720 

0 

0 

313 

5,350 

Sept. 

4,600 

180,960 

18,410 

7,600 

—1,110 

0 

0 

298 

2.350 

Oct. 

8.060 

158,440 

19,030 

4,000 

—   410 

0 

0 

287 

1,140 

Nov. 

56,600 

143,060 

18,410 

0 

+    140 

0 

0 

0 

Dec. 

92,200 

181,390 

19,030 

46,120 

+    480 

0 

0 

318 

14,660 

Total  or 
average 

1,278,230 

224,040 

346,350 

—6,160 

618,790 

0 

315 

9,480 

1910 

Jan. 

82,400 

208,920 

19,030 

46,120 

+    680 

4,850 

0 

323 

14,920 

Feb. 

52,600 

222,000 

17,190 

41,650 

+    420 

310 

0 

324 

14,930 

Mar. 

147,000 

215,870 

19,030 

46,120 

+   430 

76,150 

0 

324 

14,970 

April 

193,000 

222,000 

18,410 

44,630 

—    370 

129,590 

0 

325 

15,000 

May 

196,000 

222,000 

19,030 

46,120 

—  1,070 

129,780 

0 

325 

15,000 

June 

59,500 

222,000 

18,410 

33,210 

—1,460 

14,760 

0 

324 

11.140 

July 

10,600 

213,660 

19,030 

10,600 

—1,930 

0 

0 

316 

3,360 

Aug. 

3,960 

192,700 

19,030 

3.960 

—1,550 

0 

0 

306 

1,210 

Sept. 

4,420 

172,120 

18,410 

4.420 

—    990 

0 

0 

294 

1,350 

Oct. 

6,580 

152,720 

19,030 

3,000 

—   390 

0 

0 

283 

850 

Nov. 

10,100 

136,880 

18,410 

0 

+    120 

0 

0 

0 

Dec. 
Total  or 
average 

21,900 

128,690 

19,030 

0 

+    370 

0 

0 

0 

788,060 

224,040 

279,830 

—5,740 

355,440 

0 

314 

7,670 

1911 

Jan. 

148,000 

131,930 

19,030 

8,120 

+    470 

31,250 

0 

286 

2,430 

Feb. 

143,000 

222,000 

17,190 

41,650 

+    420 

84,580 

0 

325 

15,000 

Mar. 

204,000 

222,000 

19,030 

46,120 

+    430 

139,280 

0 

325 

15,000 

April 
May 

256,000 

222,000 

18,410 

44,630 

—    370 

102,590 

0 

325 

15,000 

262,000 

222,000 

19,030 

46,120- 

—1.070 

195,780 

0 

325 

15,000 

June 

331,000 

222,000 

18,410 

44,630 

—1.460 

266,500 

0 

325 

15,000 

July 

117,000 

222,000 

19,030 

40,400 

—1,930 

60,270 

0 

325 

13.130 

Aug. 

16,500 

217,370 

19,030 

26,500 

—1,720 

0 

0 

315 

8,360 

S*pt. 

0,280 

186.620 

18,410 

11.500 

—1,110 

0 

0 

302 

3, .580 

Oct. 

8,790 

164,880 

19,030 

4,000 

—   410 

0 

0 

290 

1,170 

Nov. 

11.900 

150.230 

18,410 

0 

-1-    140 

0 

0 

0 

Dec. 
1  otai  or 

8,360 
1,515,830 

143,860 

19,030 

2,000 

+    400 

0 

0 

278 

560 

average 

224,040 

315,670 

-6,210 

970,250 

0 

311 

8,630 

1912 

Jan. 

14,000 

131,590 

19,030 

2,920 

+   490 

0 

0 

272 

790 

Feb. 

10,800 

124,130 

17,800 

8,000 

4-  300 

0 

0 

263 

2,260 

Mar. 

21,000 

109.430 

19,030 

24,000 

+    290 

0 

0 

249 

5.980 

April 
May 

30,800 

87,690 

18,410 

34,000 

—   230 

0 

0 

229 

8,040 

140,000 

65,850 

19,030 

31,000 

—   600 

0 

0 

247 

7,650 

June 

125,000 

155,220 

18,410 

33,020 

—1,250 

10,360 

0 

319 

10.920 

July 

9,900 

217,180 

19.030 

9,900 

—1,930 

0 

(1 

318 

3,1.50 

Aug. 

5,580 

1116.220 

19,030 

5,580 

—1,550 

0 

0 

307 

1,720 

Sept. 

6,000 

175,640 

18,410 

6.600 

—   090 

0 

0 

296 

2.010 

Oct. 

5,260 

156,240 

19,030 

3,000 

—   390 

0 

0 

285 

860 

Nov. 

31,100 

139.080 

18.410 

0 

+    120 

0 

(1 

0 

Deo. 
ToUl  or 
average 

10,500 

151,890 

19.030 

11,000 

+    400 

0 

0 

281 

3,090 

410..540 

224,650 

169,020 

—5,340 

10,360 

0 

279 

3,870 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


303 


VOIR  ON  MOKELUMNE  RIVER. 

FLOOD  CONTROL  BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  6,  page  124.) 

Yield  in  municipal  supply  200  million  gallons  daily. 
Installed  capacity  of  power  plant  15,000  k.w. 


Coordinated 

with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Clements — rain-water  floods 

5.300  sec.-ft 

.;  snow-water  floods.  7,100  sec.-ft. 

Maximum  reservoir  space  required — rain-water  floods,  92,000  ac.-ft.; 

snow-water  floods,  13,00C 

ac.-ft. 

Power 

Stage  of 

draft 
through 

Release 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

Average 
power 

Average 

Year  and 

reservoir 

at 
beginning 

ot 
month  in 
acre-feei 

Municipal 

draft 

in 

acre-feet 

turbines 
including 
water 
passed 
for  prior 
rights  in 

Evapora- 
tion in 
acre-feet 

through 

flood 

control 

outlets  in 

acre-feet 

in 

municipal 

supply 

in 
acre-feet 

head 

through 

period 

of 

operation 

in  feet 

power 
yield  in 
kilowatts 

(Load 
factor= 

1.00) 

month 

acre-feet 

1909 

126,030 

19,030 

20,990 

+    440 

10^,260 

0 

0 

294 

6,530 

Jan. 

160,190 

17.190 

48.870 

+   420 

87,310 

0 

0 

277 

15,000 

Feb. 

133.240 

19,030 

42,020 

+   430 

13,700 

0 

0 

282 

11,770 

Mar. 

161.920 

18,410 

35,940 

—   370 

12,220 

39,980 

0 

313 

11,750 

April 

222,000 

19,030 

46,430 

—1,070 

99,300 

74,470 

0 

323 

15,000 

May 

209,700 

18,410 

45,270 

—1,460 

184,310 

0 

0 

321 

15,000 

June 

216,250 

19,030 

30.130 

—1,930 

4,150 

0 

0 

324 

9.770 

July 

211,710 

19,030 

17,070 

—1,720 

0 

0 

0 

313 

5,350 

Aug. 

180,960 

18,410 

7,600 

—1,110 

0 

0 

0 

298 

2,350 

Sept. 

158.440 

19,030 

4.000 

—   410 

0 

0 

0 

287 

1,140 

Oct. 

143,060 

18,410 

0 

+    140 

0 

0 

0 

0 

Nov. 

181,390 

19,030 

47,500 

+    480 

46,730 

0 

0 

312 

14,800 

Dec. 
Total  or 

224,040 

345,820 

—6,160 

5.52,980 

114,450 

0 

304 

9,010 

averag3 
1910 

160,810 

19,030 

45,580 

+   680 

44,650 

0 

0 

286 

13,170 

Jan. 

134,630 

17,190 

32,330 

+   420 

3,400 

0 

0 

275 

9,850 

Feb. 

134.730 

19,030 

47,610 

+   430 

47.070 

0 

0 

287 

13,640 

Mar. 

168,450 

18,410 

42,440 

—    370 

22.560 

55,670 

0 

315 

13,860 

April 

222,000 

19,030 

46.380 

—1,070 

92,040 

47,990 

0 

323 

15,000 

May 

211,490 

18.410 

33,310 

—1,460 

14,690 

0 

0 

319 

10,920 

June 

203.120 

19.030 

10,600 

—1,930 

0 

0 

0 

310 

3,290 

July 

182,160 

19,030 

3,960 

—1,550 

0 

0 

0 

299 

1,180 

Aug. 

161,580 

18,410 

4,420 

—    990 

0 

0 

0 

287 

1,310 

Sept. 

142,180 

19,030 

3,000 

—    390 

0 

0 

0 

276 

820 

Oct. 

126,340 

18,410 

0 

+    120 

0 

0 

0 

0 

Nov. 

118,150 

19,030 

0 

+    370 

0 

0 

0 

0 

Dec. 
Total  or 

224,040 

269.630 

—5,740 

224,410 

103,660 

0 

298 

6,900 

average 
1911 

121,390 

19,030 

18,120 

+    470 

52,820 

0 

0 

275 

5,090 

Jan. 

179,890 

17.190 

47,070 

+    420 

125,410 

0 

0 

286 

14,910 

Feb. 

133,640 

19,030 

52.540 

+    430 

102.620 

0 

0 

286 

15,000 

Mar. 

163.880 

18.410 

46,240 

—   370 

78.010 

£4,850 

0 

314 

15,000 

April 

222,000 

19,030 

46,160 

—1,070 

97,820 

103,280 

0 

325 

15,000 

May 

216,640 

18,410 

44,870 

—1,460 

262,490 

0 

0 

.323 

15,000 

June 

220,410 

19,030 

40,400 

—1,930 

11,260 

47,420 

0 

325 

13,130 

July 

217,370 

19,030 

26,500 

—1,720 

0 

0 

0 

315 

8,360 

Aug. 

186,620 

18,410 

11,500 

—1,110 

0 

0 

0 

302 

3,580 

Sept. 

164,880 

19,030 

4,000 

—   410 

0 

0 

0 

290 

1,170 

Oct. 

150,230 

18.410 

0 

-1-    140 

0 

0 

0 

0 

Nov. 

143,860 

19,030 

2,000 

+   400 

0 

0 

0 

278 

550 

Dec. 

Tntal  nr 

224,040 

339,400 

—6,210 

730,4.30 

205,.550 

0 

302 

8,8.50 

XKJbal  Ul 

average 
1912 

131,590 

19,030 

2.920 

+   490 

0 

0 

0 

272 

790 

Jan. 

124,130 

17,800 

8,000 

+   300 

0 

0 

0 

263 

2,200 

Feb. 

109,430 

19,030 

24,000 

+    290 

0 

0 

0 

249 

5,980 

Mar. 

87,690 

18,410 

34.000 

-   230 

0 

0 

0 

229 

8,040 

April 

65.8.50 

19,030 

31.000 

—   600 

0 

0 

0 

247 

7,650 

May 

155,220 

18.410 

33.020 

—1,250 

0 

10,360 

0 

319 

10,920 

June 

217,180 

19,030 

9,900 

—1,930 

0 

0 

0 

318 

3,150 

July 

196,220 

19,030 

5,580 

—1,550 

0 

0 

0 

307 

1,720 

Aug. 

175,640 

18,410 

6,600 

—   990 

0 

0 

0 

296 

2,010 

Sept. 

156,240 

19.0.30 

3,000 

—    390 

0 

0 

0 

285 

860 

Oct. 

139.080 

18.410 

0 

+    120 

0 

0 

0 

0 

Nov. 

151.890 

19.030 

11,000 

+   400 

0 

0 

0 

28i 

3,090 

Dec. 
Total  or 
average 

224,650 

169,020 

—5,340 

0 

10,360 

0 

279 

3,870 

304 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  6a  (Continued).     PARDEE  RESER 

WATER  AND  POWER  YIELD  BOTH  WITH  AND  WITHOUT 

Monthly  Summary  of  Computa 

(For  corresp)onding  yearly  sum 


Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


Run-off 

at 
Clements 

in 
acre-feet 

Without  flood  control 

Year  and 
month 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

Power 

draft 

through 

turbines 

including 

water 

passed 

for  prior 

rights  in 

Evapora- 
tion in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 
through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

acre-feet 

1913 

Jan. 

22,600 

132,760 

19,030 

2,500 

-I-   490 

0 

0 

274 

690 

Feb. 

19,800 

134,320 

17,190 

18,500 

+    300 

0 

0 

271 

5.540 

Mar. 

21,600 

118,730 

19,030 

34,770 

+    310 

0 

0 

252 

8.760 

April 

83,900 

86,840 

18,410 

35,000 

—   260 

0 

0 

247 

8,930 

May 

148,000 

117,070 

19,030 

32,060 

—   830 

0 

0 

292 

9,370 

June 

55,300 

213,1.50 

18,410 

32,210 

—1.460 

3,280 

0 

324 

10,790 

July 

10,500 

213,090 

19,030 

10.-500 

—1.930 

0 

0 

316 

3,320 

Aug. 

8.360 

192,130 

19,030 

8,360 

—  1,550 

0 

0 

305 

2,550 

Sept. 

6.370 

171.550 

18,410 

6.370 

—    990 

0 

0 

293 

1,930 

Oct. 

7,130 

152,150 

19,030 

3,000 

—    390 

0 

0 

282 

850 

Nov. 

8,090 

136.860 

18,410 

0 

+    130 

0 

0 

0 

Dec. 
Total  or 
average 

14,300 

126,670 

19,030 

0 

+   360 

0 

0 

0 

405,950 

224,040 

183,270 

—5,820 

3,280 

0 

286 

4,370 

1914 

Jan. 

169,000 

122.300 

19,030 

10,140 

+   450 

40,580 

0 

301 

3,270 

Feb. 

102,000 

222,000 

17,190 

41,050 

+   420 

43,580 

0 

325 

15.000 

Mar. 

105,000 

222,000 

19,030 

46,120 

-t-   430 

40,280 

0 

325 

l&.OOO 

April 

144,000 

222,000 

18,410 

44.630 

—   370 

80,590 

0 

325 

15,000 

May 

261,000 

222,000 

19,030 

46,120 

—1,070 

194,780 

0 

325 

15,000 

June 

198,000 

222,000 

18,410 

44,630 

—1,460 

133,500 

0 

325 

15,000 

July 

50,200 

222,000 

19,030 

31,320 

—1,930 

8.010 

0 

324 

10.160 

Aug. 

10,200 

211,910 

19,030 

20,200 

—1,720 

0 

0 

313 

6.330 

Sept. 

7,800 

181,160 

18,410 

10,800 

—1,110 

0 

0 

298 

3.330 

Oct. 

8,120 

158,640 

19,030 

7,000 

—   410 

0 

0 

286 

2.000 

Nov. 

7,970 

140,320 

18,410 

0 

+    140 

0 

0 

0 

Dec. 
Total  or 
average 

12,600 

130,020 

19,030 

0 

-1-   390 

0 

0 

0 

1,075,890 

224.040 

302,610 

—6,240 

541,320 

0 

314 

8.280 

1915 

Jan. 

19,600 

123,980 

19,030 

1,500 

+  490 

0 

0 

269 

400 

Feb. 

75,000 

123,540 

17,190 

13,500 

+  30O 

0 

0 

286 

4,270 

Mar. 

61,400 

168,150 

19.030 

46,120 

4-  390 

0 

0 

293 

13,490 

April 

133,000 

164,790 

18.410 

44,630 

—   370 

12,380 

0 

310 

14.310 

May 

218,000 

222,000 

19.030 

46,120 

—1,070 

151,780 

0 

325 

15,000 

June 

231,000 

222,000 

18,410 

44,630 

—1,460 

166.500 

0 

325 

15,000 

July 

44.000 

222,000 

19,030 

28,700 

—1,930 

5,800 

0 

324 

9,300 

Aug. 

5.710 

210,540 

19,030 

9,710 

—1,630 

0 

0 

314 

3.050 

Sept. 

6,370 

185.880 

18,410 

9.370 

-1.050 

0 

0 

300 

2.920 

Oct. 

6.830 

163.420 

19,030 

4,000 

—   400 

0 

0 

289 

1,160 

Nov. 

8.690 

140.820 

18,410 

0 

+    130 

0 

0 

0 

Deo. 
Total  or 
average 

19.800 

137.230 

19,030 

0 

+   390 

0 

0 

0 

829.400 

224.040 

248,280 

—6,210 

336.460 

0 

303 

6.580 

1916 

Jan. 

79.300 

138.390 

19,030 

6,500 

-1-    490 

0 

0 

290 

1.900 

Feb. 

97.800 

192,650 

17,800 

43,140 

+   400 

7,910 

0 

319 

14,740 

Mar. 

176.000 

222,000 

19.030 

46,120 

+   430 

110,280 

0 

325 

15.000 

April 
May 

196.000 

222,000 

18,410 

44,630 

—   370 

131,590 

0 

326 

15,000 

205,000 

222,000 

19.030 

46,120 

—1.070 

138,780 

0 

325 

15,000 

June 

181,000 

222,000 

18.410 

44.630 

-1,460 

116,500 

0 

326 

15,000 

July 

46.900 

222,000 

19.030 

32.390 

—1,930 

3.800 

0 

324 

10,600 

Aug. 

10.600 

211.760 

10.030 

19.500 

—1,720 

0 

0 

313 

6.100 

Sept. 

6.720 

182.000 

18.410 

9,720 

—1,110 

0 

0 

299 

3.000 

Oct. 

12,700 

160,480 

19.030 

6.000 

—   410 

0 

0 

288 

1,730 

Nov. 

11.800 

146.740 

18.410 

4,000 

+    140 

0 

0 

280 

1,170 

Dec. 
ToUl  or 
average 

27,600 

136,270 

19,030 

1,000 

+   400 

0 

0 

282 

280 

1,049,320 

224,650 

303,750 

-6.210 

508,860 

0 

308 

8,240 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


305 


VOIR  ON  MOKELUMNE  RIVER. 

FLOOD  CONTROL  BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  6,  page  124.) 

Yield  in  municipal  supply  200  million  gallons  daily. 
Installed  capacity  of  power  plant  15,000  k.w. 


Coordinated  with  flood  control  by  reservoir  operatinq  diaqram 

Maximum  controlled  flow  at  Clements — rain- 

water  floods 

5,300  sec.-f t, ;  snow-water  floods.  7.100  sec.-f t. 

Maximum  reservoir  space  required — rain-water  floods,  92,000  ac.-ft.; 

snow-water  floods,  13,000  ac.-ft. 

Power 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

draft 
through 
turbines 
including 
water 
passed 
for  prior 
rights  in 
acre-feet 

Evapora- 
tion in 
acre-feet 

Release 

through 

flood 

control 
outlets  in 
acre-feet 

Waste 

over 

spillway 

in 

acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

Year  and 
month 

132,760 

19,030 

2,500 

+   490 

0 

0 

0 

274 

690 

1913 

Jan. 

134.320 

17,190 

18,500 

+    300 

0 

0 

0 

271 

5,540 

Feb. 

118,730 

19,030 

34,770 

+   310 

0 

0 

0 

252 

8,760 

Mar. 

86,840 

18,410 

35,000 

—   260 

0 

0 

0 

247 

8,930 

April 

117,070 

19,030 

32,060 

—   830 

0 

0 

0 

292 

9,370 

May 

213,150 

18,410 

32,210 

—  1,460 

0 

3,280 

0 

324 

10,790 

June 

213,090 

19,030 

10,500 

—1,930 

0 

0 

0 

316 

3,320 

July 

192,130 

19,030 

8,360 

—1,5.50 

0 

0 

0 

305 

2,5.50 

Aug. 

171,550 

18,410 

6,370 

—   990 

0 

0 

0 

293 

1,930 

Sept. 

152,150 

19,0.30 

3,000 

—    390 

0 

0 

0 

282 

850 

Oct. 

136,800 

18,410 

0 

+    130 

0 

0 

0 

0 

Nov. 

126,670 

19,030 

0 

+   360 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

183,270 

—5,820 

0 

3,280 

0 

286 

4,370 

122,300 

19,030 

39,510 

+   450 

95,510 

0 

0 

283 

11,160 

1914 

Jan. 

137,700 

17,190 

42,430 

+   420 

48,850 

0 

0 

275 

12,920 

Feb. 

131,650 

19,030 

45,680 

+   430 

6,190 

0 

0 

283 

12,840 

Mar. 

166,180 

18,410 

39,980 

—  370 

17,370 

12,050 

0 

314 

13,060 

April 

22i;,000 

19,030 

46,430 

—1,070 

152,780 

53,790 

0 

323 

15,000 

May 

209,900 

18,410 

45,270 

—1,460 

126,510 

0 

0 

320 

15,000 

June 

216,250 

19,0.30 

30,790 

—1,930 

1,900 

890 

0 

324 

10,130 

July 

211,910 

19,030 

20,200 

—1,720 

0 

0 

0 

313 

6,330 

Aug. 

181,160 

18,410 

10,800 

—1,110 

0 

0 

0 

298 

3,330 

Sept. 

158,640 

19,030 

7,000 

—   410 

0 

0 

0 

286 

2,000 

Oct. 

140,320 

18,410 

0 

+    140 

0 

0 

0 

0 

Nov. 

130,020 

19,030 

0 

+   390 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

328,090 

—6,240 

449,110 

66,730 

0 

302 

8,450 

123,980 

19,030 

1,500 

+   490 

0 

0 

0 

269 

400 

1915 

Jan. 

123,540 

17,190 

22,210 

+   300 

17,270 

0 

0 

278 

6,860 

Feb. 

142,170 

19,030 

18,950 

+   390 

1,190 

0 

0 

286 

5,480 

Mar. 

164,700 

18,410 

44,630 

—   370 

12,.380 

0 

0 

310 

14,310 

April 

222,000 

19,030 

46,410 

—1,070 

142,010 

20,690 

0 

323 

15,000 

May 

210,790 

18,410 

45,230 

—1,460 

159,450 

0 

0 

321 

15,000 

June 

217,240 

19,0.30 

28,130 

—1,930 

1,270 

340 

0 

323 

9,130 

July 

210,.540 

19,030 

9,710 

—1,6.30 

0 

0 

0 

314 

3,050 

Aug. 

185,880 

18,410 

9,370 

—1,050 

0 

0 

0 

300 

2,920 

Sept. 

163,420 

19,030 

4,000 

—   400 

0 

0 

0 

289 

1,160 

Oct. 

146,820 

18,410 

0 

4-    130 

0 

0 

0 

0 

Nov. 

137,230 

19,030 

0 

+   390 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

230,140 

-0,210 

333,570 

21,030 

0 

302 

6,080 

138,390 

19,030 

30,450 

+   490 

34,170 

0 

0 

280 

8,510 

1916 

Jan. 

134,530 

17,800 

49,270 

+   400 

30,730 

0 

0 

275 

14,470 

Feb. 

134,930 

19,030 

52,940 

-f   430 

72,920 

0 

0 

283 

14,990 

Mar. 

165,470 

18,410 

44,740 

—   370 

21,790 

53,160 

0 

314 

14,510 

April 

222,000 

19,030 

46,420 

—1,070 

77,790 

72,090 

0 

323 

15,000 

May 

210,600 

18,410 

45,170 

—1,460 

109,520 

0 

0 

321 

14,970 

June 

217,010 

19,030 

30,370 

—1,930 

0 

860 

0 

324 

9,850 

July 

211,75& 

19,030 

19,500 

—1720 

0 

0 

0 

313 

0,100 

Aug. 

182,000 

18,410 

9,720 

—1,110 

0 

0 

0 

299 

3,000 

Sept. 

159,480 

19,030- 

6,000 

—   410 

•     0 

0 

0 

288 

1,730 

Oct. 

146,740 

18,410 

4,000 

+    140 

0 

0 

0 

280 

1,170 

Nov. 

136,270 

19,030 

1,000 

+   400 

0 

0 

0 

282 

280 

Dec. 
Total  or 
average 

224,650 

339,580 

-0,210 

346,920 

126.110 

0 

298 

8,090 

306 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  6a  (Continued).     PARDEE  RESER 

WATER  AND  POWER  YIELD  BOTH  WITH  AND  WITHOUT 

Monthly  Summary  of  Computa 
(For  corresponding  yearly  sum 


Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


Run-off 

at 
Clements 

in 
acre-feet 

Without  flood  control 

Year  and 
month 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-leet 

Power 

draft 

through 

turbines 

including 

water 

passed 

for  prior 

rights  in 

Evapora- 
tion in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor=^ 
1.00) 

acre-feet 

1917 

Jan. 

20.000 

144,240 

19,030 

19,500 

-f  530 

0 

0 

276 

5,390 

Feb. 

69,400 

126,240 

17.190 

15,500 

+   330 

0 

0 

270 

4,640 

Mar. 

59,500 

163,280 

19,030 

4U.120 

+   430 

0 

0 

291 

13,430 

April 

134,000 

158,060 

18,410 

44,630 

—   370 

6,650 

0 

306 

14,100 

May 

207,000 

222,000 

19,030 

46,120 

—1,070 

140,780 

0 

325 

16,000 

June 

264,000 

222.000 

18,410 

44,030 

—1,460 

199,500 

0 

326 

15.000 

July 

47,000 

222.000 

19.030 

29,530 

—1,930 

6.000 

0 

324 

9.580 

Aag. 

9,350 

2Ii,510 

19,030 

16,350 

—1,720 

0 

0 

314 

6.130 

Sept. 

5,680 

184,7ti0 

18,410 

8,680 

—1,110 

0 

0 

301 

2.690 

Oct. 

4,590 

162,240 

19,030 

x.OOO 

—   410 

0 

0 

288 

1.160 

Nov. 

6,110 

143.390 

18,410 

0 

+   130 

0 

0 

0 

Dec. 

3,230 

130,220 

19,030 

0 

-1-   390 

0 

0 

0 

Total  or 
avercge 

828,860 

224,040 

275,060 

—6,260 

352,930 

0 

302 

7.190 

1918 

Jan. 

3,170 

114,810 

19,030 

1,500 

+   450 

0 

0 

255 

380 

Feb. 

19,400 

97,900 

17,190 

9,760 

-f-   250 

0 

0 

242 

2,620 

Mar: 

106,000 

90,600 

19,030 

15,000 

+   250 

0 

0 

266 

3,990 

April 

122,000 

162,820 

18,410 

44,630 

—   300 

0 

0 

306 

14.100 

May 

148,000 

221,480 

19,030 

46,129 

—1,070 

81,260 

0 

325 

15.000 

June 

87,500 

222,000 

18,410 

37,660 

—1,460 

35,420 

0 

325 

12.640 

July 

7,930 

216,550 

19,030 

7,930 

—1,930 

0 

0 

317 

2,510 

Aug. 

4,860 

195.590 

19,030 

4,860 

—1,550 

0 

0 

307 

1,490 

Sept. 

8,810 

176.010 

18,410 

8,810 

—   990 

0 

0 

295 

2,690 

Oct. 

13,700 

155.610 

19,030 

3,000 

—   390 

0 

0 

287 

860 

Nov. 

12,300 

146.890 

18,410 

0 

-f    130 

0 

0 

0 

Dec. 

Total  or 

12,500 

140,910 

19.030 

0 

+   390 

0 

0 

0 

average 

546,170 

224,040 

179,270 

—6,220 

116,680 

0 

293 

4,680 

1919 

.Ian. 

10,300 

134.770 

19,030 

6,000 

-f   470 

0 

0 

271 

1,630 

Fob. 

47.100 

120,510 

17.190 

10,500 

+   280 

0 

0 

272 

3,150 

Mar. 

51.500 

140.200 

19,030 

46.120 

+   310 

0 

0 

273 

12,590 

April 

146.000 

126.860 

18.410 

44,630 

—  280 

0 

0 

291 

13.400 

May 

247.000 

209,540 

19.030 

46,120 

—1,070 

168.320 

0 

326 

15,000 

June 

33.800 

222,000 

18,410 

24.270 

—1,460 

3.250 

0 

323 

8,130 

July 

5.560 

208,410 

19,030 

5.560 

-1,740 

0 

0 

313 

1,750 

Aug. 

4.930 

187,640 

19,030 

4.930 

—1,380 

0 

0 

303 

1,490 

Sept. 

5.180 

167,230 

18,410 

5.180 

—   930 

0 

0 

291 

1,560 

Oct. 

4,690 

147,890 

19,030 

3.000 

-  360 

0 

0 

279 

830 

Nov. 

5,270 

130,190 

18,410 

0 

-f-    120 

0 

0 

0 

Dec. 
Total  or 
average 

11,800 

117.170 

19,030 

0 

+  320 

0 

0 

0 

573,130 

224.040 

196.310 

—5.720 

171.670 

0 

294 

4,970 

1920 

Jan. 

7.810 

110.260 

19,030 

1.500 

-1-   390 

0 

0 

254 

380 

Feb. 

8,230 

97.930 

17,800 

2.500 

-f-  230 

0 

0 

243 

650 

Mar. 

43,600 

86.090 

19,030 

19.380 

-f   220 

0 

0 

241 

4,680 

April 

88,700 

91.500 

18,410 

35,000 

—   190 

0 

0 

252 

9,110 

May 

191,000 

126,600 

19,030 

35,880 

—  720 

39.970 

0 

304 

10.990 

June 

78,500 

22:^,000 

18,410 

38,240 

—1,460 

24.370 

0 

326 

12,830 

July 

13,800 

218,020 

19.030 

13.800 

—1,930 

0 

u 

318 

4.400 

Aug. 

6,840 

197,060 

19.030 

6.840 

—1,550 

0 

0 

308 

1.800 

Sept. 

4.840 

176.480 

18,410 

4,840 

—  990 

0 

0 

296 

1.490 

Oct. 

9.690 

167.080 

19.030 

3,000 

—  390 

0 

0 

286 

860 

Nov. 

19,900 

144.250 

18.410 

0 

+   130 

0 

0 

0 

Dec. 
Total  or 
average 

34,500 

145,870 

19,030 

0 

+  390 

0 

0 

0 

606,310 

224,650 

169,980 

—5,870 

64.340 

0 

283 

3,930 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


307 


VOIR  ON  MOKELUMNE  RIVER. 

FLOOD  CONTROL  BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  6,  page  124.) 

Yield  in  municipal  supply  200  million  gallons  daily. 
Installed  capacity  of  power  plant  15,000  k.w. 


Coordinated  with  flood  control  by  reservoir  operatinq  diaqram 

Maximum  controlled  flow  at  Clements— rain 

-water  floodf 

,  5,300  sec- 

t.;  snow-water  floods,  7,100  sec.-ft. 

Maximum  reservoir  spacs  requited — rain-water  floods,  i 

i,000  ac.-ft. 

snow-water  floods,  13,000  ac.-ft. 

Power 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municip!.! 

draft 
through 
turbines 

Evapora- 
tion in 
acre-feet 

Release 
through 

Waste 

Deficie  ncy 
in 

Average 
power 
head 

Average 
power 

yield  in 

kilowatts 
(Load 

facto  r= 
1.00) 

Year  and 

drait 

in 

acre-feet 

including 

water 

passed 

for  prior 

rights  in 

flood 

control 

outlets  in 

acre-feet 

over 
spillway 

in 
acre-feet 

municipal 
supply 

in 
acre-feet 

through 

period 

of 

operation 

in  feet 

month 

acre-feet 

144,240 

19,030 

19,500 

-f   530 

0 

0 

0 

27G 

5,390 

1917 

Jan. 

126,240 

17,190 

17,750 

+   330 

13,790 

0 

0 

270 

5,360 

Feb. 

147,240 

19.030 

28,180 

+  430 

1,900 

0 

0 

288 

8,150 

Mar. 

158,060 

18,410 

44,630 

—  370 

0 

6,650 

0 

306 

14,100 

April 

222,000 

19,030 

46,180 

—1,070 

59,840 

85,440 

0 

325 

15,000 

May 

217,440 

18,410 

44,750 

—1,460 

187,820 

7,000 

0 

324 

15,000 

June 

222,000 

19,030 

29,530 

—1,930 

0 

6,000 

0 

324 

9,580 

July 

212,510 

19,030 

16,350 

—1,720 

0 

0 

0 

314 

5,130 

Aug. 

184,760 

18,410 

8,680 

—1,110 

0 

0 

0 

301 

2,690 

Sept. 

162,240 

19,030 

4,000 

—   410 

0 

0 

0 

288 

1,160 

Oct. 

143,390 

18,410 

0 

+    130 

0 

0 

0 

0 

Nov. 

130,220 

19,030 

0 

+   390 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

259,550 

—6,260 

263,350 

105,090 

0 

302 

6,790 

114,810 

19,030 

1,500 

-f   450 

0 

0 

0 

255 

380 

1918 

Jan. 

97,900 

17,190 

9,760 

+   250 

0 

0 

0 

242 

2,620 

Feb. 

90,600 

19,030 

15.000 

-t-   250 

0 

0 

0 

256 

3,990 

Mar. 

162,820 

18,4)0 

44,630 

—   300 

0 

0 

0 

306 

14,100 

April 

221,480 

19,030 

46,120 

—1,070 

0 

81,260 

0 

325 

15,000 

May 

222,000 

18,410 

37,660 

—1,460 

0 

35,420 

0 

325 

12,640 

June 

216,550 

19,030 

7,930 

—1,930 

0 

0 

0 

317 

2,510 

July 

195,590 

19,030 

4,860 

—1,550 

0 

0 

0 

307 

1,490 

Aug. 

175,010 

18.410 

8,810 

—   990 

0 

0 

0 

295 

2,690 

Sept. 

155,610 

19,030 

3,000 

—   390 

0 

0 

0 

287 

860 

Oct. 

146,890 

18,410 

0 

4-    130 

0 

0 

0 

0 

Nov. 

140,910 

19,030 

0 

-h   390 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

179,270 

—6,220 

0 

116,680 

0 

293 

4,680 

1919 

134,770 

19,030 

6,000 

+  470 

0 

0 

0 

271 

1,630 

Jan. 

120,510 

17,190 

10,500 

4-   280 

0 

0 

0 

272 

3,150 

Feb. 

140,200 

19,030 

46,120 

+  310 

0 

0 

0 

273 

12,590 

Mar. 

126,860 

18,410 

44,630 

—  280 

0 

0 

0 

291 

13,400 

April 

209,540 

19,030 

46,120 

—1,070 

0 

168,320 

0 

325 

15,000 

May 

222,000 

18,410 

24,270 

—1,460 

0 

3,250 

0 

323 

8,130 

June 

208,410 

19,030 

5,560 

—1,740 

0 

0 

0 

313 

1.750 

July 

187,640 

19,030 

4,930 

—1,380 

0 

0 

0 

303 

1,490 

Aug. 

167,230 

18,410 

5,180 

—   930 

0 

0 

0 

291 

1,560 

Sept. 

147,890 

19,030 

3,000 

—   360 

0 

0 

0 

279 

830 

Oct. 

130,190 

18,410 

0 

+    120 

0 

0 

0 

0 

Nov. 

117,170 

19,030 

0 

+   320 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

196,310 

-5.720 

0 

171,570 

0 

294 

4,970 

1920 

110,260 

19,030 

1,500 

+  390 

0 

0 

0 

254 

380 

Jan. 

97,930 

17,800 

2,500 

+  230 

0 

0 

0 

243 

650 

Feb. 

86,090 

19,030 

19,380 

-1-   220 

0 

0 

0 

241 

4,680 

Mar. 

91,500 

18,410 

35,000 

—    190 

0 

0 

0 

252 

9,110 

April 

126,600 

19,030 

35,880 

—   720 

0 

39,970 

0 

304 

10,990 

May 

222,000 

18,410 

38,240 

—1,460 

0 

24,370 

0 

325 

12,830 

June 

218,020 

19,030 

13,800 

—1,930 

0 

0 

0 

318 

4,400 

July 

197,060 

19,030 

5,840 

—1,550 

0 

0 

0 

308 

1,800 

Aug. 

176,480 

18,410 

4,840 

—    990 

0 

0 

0 

298 

1,490 

Sept. 

157,080 

19.030 

3,000 

-   390 

0 

0 

0 

286 

860 

Oct. 

144,250 

18,410 

0 

-f    130 

0 

0 

0 

0 

Nov. 

145,870 

19,030 

0 

+   390 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,650 

159,980 

—5,870 

0 

64,340 

0 

283 

3.930 

308 


WATER  RESOURCES   OF   CALIFORNIA. 


TABLE  6a  (Continued).     PARDEE  RESER 

WATER  AND  POWER  YIELD  BOTH  WITH  AND  WITHOUT 

Monthly  Summary  of  Computa 
(For  corresponding  yearly  sum 

Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


- 

Run-off 

at 
Clements 

in 
acre-feet 

Without  flood  control 

Year  and 
month 

Stage  of 
reservou- 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

Power 

draft 

through 

turbines 

including 

water 

passed 

for  prior 

rights  in 

Evapora- 
tion in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

jneld  in 

kilowatts 
(Load 

factor=: 
1.00) 

acre-feet 

1921 

Jan. 

78,700 

161,730 

19.030 

25.500 

+   530 

0 

0 

300 

7.030 

Feb. 

6i,100 

196.430 

17,190 

41.650 

-1-  420 

0 

0 

312 

14,420 

Mar. 

108,000 

199,110 

19,030 

46.120 

+   430 

20,390 

0 

323 

14,910 

April 

123,000 

222,000 

18,410 

44,630 

—   370 

69.590 

0 

325 

15.000 

May 

218,000 

222,000 

19,030 

46.120 

—1,070 

151.780 

0 

325 

15.000 

June 

178,000 

222,000 

18.410 

44,630 

—1,460 

113.500 

0 

325 

15.000 

July 

20,400 

222.000 

19.030 

17,610 

—1,930 

280 

0 

321 

5.690 

Aug. 

7,750 

203.550 

19.030 

7,750 

—1,550 

0 

0 

311 

2.410 

Sept. 

5,710 

182,970 

18.410 

5,710 

—   990 

0 

0 

300 

1.780 

Oct. 

7.190 

163.570 

19,030 

3,000 

—   390 

0 

0 

289 

870 

Nov. 

4,530 

148,340 

18,410 

0 

+    130 

0 

0 

0 

Dec. 
Total  or 
average 

10,900 

134,590 

19,030 

0 

+   360 

0 

0 

0 

823,280 

224,040 

282,720 

—5.890 

345,540 

0 

313 

7.660 

1922 

Jan. 

19,200 

126,820 

19,030 

1,500 

-f   440 

0 

0 

272 

400 

Feb. 

58.900 

125,930 

17,190 

3,000 

+   270 

0 

0 

280 

940 

Mar. 

56,500 

164,010 

19,030 

46,120 

-f-   330 

0 

0 

288 

13,310 

April 

107,000 

156,590 

18,410 

44,630 

—   320 

0 

0 

297 

13.690 

May 

318,000 

200,230 

19,030 

46,120 

—1.070 

230,010 

0 

325 

14.970 

Junj 

280,000 

222,000 

18.410 

44.630 

—1.460 

215,500 

0 

325 

15.000 

July 

39,200 

222,000 

19,030 

27,470 

—1,930 

5,030 

0 

323 

8.900 

Auc 

10,100 

207,740 

19,030 

15,100 

—1,630 

0 

0 

312 

4.720 

Sept. 

7,620 

182,080 

18,410 

10.620 

—1,050 

0 

0 

299 

3.280 

Oct. 

7,990 

159,020 

19.030 

4.000 

—   400 

0 

0 

287 

1.140 

Nov. 

10,700 

144,180 

18,410 

0 

-f-    130 

0 

0 

0 

Dec. 
Total  or 
average 

58,800 

136.600 

19.030 

0 

+   390 

0 

0 

0 

974,010 

224,040 

243,190 

—6.300 

450,540 

0 

301 

6.390 

1923 

Jan. 

46,200 

176,760 

19,030 

46.120 

-f-   580 

0 

0 

294 

13.560 

Feb. 

33.300 

158,390 

17,190 

41.650 

+   420 

0 

0 

283 

13.050 

Mar. 

43,300 

133,270 

19,030 

46,120 

-+-   430 

0 

0 

268 

12.340 

April 
.May 

127,000 

111,850 

18,410 

44,630 

—   370 

0 

0 

282 

13.010 

225,000 

175,440 

19,030 

46,120 

—1.070 

112,220 

0 

321 

14.790 

June 

104,000 

222,000 

18.410 

44.630 

-1.460 

39,500 

0 

325 

15.000 

July 

28.500 

222,000 

19.030 

22,660 

—1.930 

770 

0 

322 

7.330 

Aug. 

9,100 

206,110 

19,030 

9,100 

—1.550 

0 

0 

312 

2,850 

Sept. 

9.040 

185,530 

18,410 

0,040 

—   990 

0 

0 

302 

2,820 

Oct. 

9,410 

166,130 

19.030 

3,000 

—   390 

0 

0 

292 

870 

Nov. 

7,080 

153,120 

18,410 

0 

+    120 

0 

0 

0 

Dec. 
Total  or 
average 

6,950 

141.910 

19.030 

0 

+   350 

0 

0 

0 

648,880 

224.040 

313,070 

-5.860 

152.490 

0 

300 

7,930 

1924 

Jan. 

8,670 

130.180 

19.030 

8,670 

+   390 

0 

0 

267 

2,310 

Feb. 

15,900 

111.540 

17.800 

15,900 

+   210 

0 

0 

252 

4,300 

Mar. 

11,200 

93.950 

19,030 

11,200 

+   200 

0 

0 

237 

2,650 

April 
May 

53.100 

75.120 

18,410 

30,000 

—    140 

0 

0 

225 

6,970 

60,900 

79.670 

19,030 

31,000 

—   420 

0 

0 

245 

7,580 

June 

4,210 

90.120 

18,410 

4,210 

—   640 

0 

0 

233 

1,010 

July 

1,220 

71.070 

19.030 

1,220 

—   690 

0 

0 

213 

260 

Aug. 

330 

61.350 

19,030 

330 

—   450 

0 

0 

186 

70 

Sept. 

2,980 

31.870 

6.770 

2,980 

—   270 

0 

11,640 

161 

500 

Oct. 

6,340 

24.830 

0 

6.340 

—    110 

0 

19,030 

159 

850 

Nov. 

18,200 

24.720 

0 

18,200 

+     40 

0 

18,410 

159 

2,990 

Dec. 
Total  or 

24,600 

24.760 

9.470 

10.950 

-f    120 

0 

9,560 

159 

1.750 

average 

206.650 

160,010 

140,000 

-1.760 

0 

58.640 

208 

2,590 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


309 


VOIR  ON  MOKELUMNE  RIVER. 

FLOOD  CONTROL  BY  RESERVOIR  OPERATING  DIAGRAM. 

tions  Carried  out  on  a  Daily  Basis. 
mary,  see  Table  6,  page  124.) 

Yield  in  municipal  supply  200  million  gallons  daily. 
Installed  capacity  of  power  plant  15,000  k.w. 


Coordinated  with  flood  contr.ol  by  reservoir  operatinc  diagram 

Maximum  controlled  flow  at  Clements — rain- 

water  floods 

,  5,300  sec.-ft.;  snow-water  floods,  7,100  sec.-ft. 

Maximum  reservoir  space  required — rain-water  floods,  S 

2,000  ac.-ft.; 

snow-water  floods,  13,000  ac.-ft. 

Power 

Stage  of 
reservoir 

at  _ 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 
through 
turbines 

Evapora- 
tion in 
acre-feet 

Release 
through 

Waste 

Deficiency 
in 

Average 
power 
head 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

Year  and 
month 

draft 

in 

acre-feet 

including 

water 

passed 

for  prior 

rights  in 

flood 

control 

outlets  in 

acre-feet 

over 
spillway 

in 
acre-feet 

municipal 
supply 

in 
acre-feet 

through 

period 

of 

operation 

in  feet 

acre-feet 

1921 

161,730 

19.030 

46,650 

+   530 

40,060 

0 

0 

283 

13,200 

Jan. 

135,220 

17,190 

38,130 

+   420 

4,710 

0 

0 

275 

11,620 

Feb. 

136,710 

19,030 

39,360 

+   430 

15,090 

0 

0 

287 

10,970 

Mar. 

171,660 

18,410 

32,610 

—   370 

21,270 

0 

0 

314 

10,400 

April 

222,000 

19,030 

46,320 

—1,070 

105,650 

55,850 

0 

324 

15.000 

May 

212,080 

18,410 

44,630 

—1,460 

106,950 

0 

0 

322 

14,850 

June 

218,030 

19,030 

16,740 

—1,930 

0 

0 

0 

320 

5,420 

July 

201, .330 

19,030 

7,750 

—1,550 

0 

0 

0 

310 

2,410 

Aug. 

180,750 

18,410 

5,710 

—   990 

0 

0 

0 

299 

1,760 

Sept. 

161,350 

19,030 

3,000 

—   390 

0 

0 

0 

288 

860 

Oct. 

146,120 

18,410 

0 

+    130 

0 

0 

0 

0 

Nov. 

132,370 

19,030 

0 

+   360 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

280,900 

—5,890 

293,730 

55,850 

0 

302 

7,170 

1922 

124,600 

19,030 

1,500 

-f   440 

0 

0 

0 

271 

400 

Jan. 

123,710 

17,190 

8,450 

-f-   270 

5,650 

0 

0 

278 

2,650 

Feb. 

151,590 

19,030 

32,800 

-t-   330 

0 

0 

0 

288 

9,790 

Mar. 

156,590 

18,410 

44,630 

—   320 

0 

0 

0 

297 

13,690 

April 

200,230 

19,030 

46,270 

—1,070 

178,710 

57,990 

0 

323 

l'*,970 

May 

215,160 

18,410 

44,940 

—1,460 

209,840 

0 

0 

323 

15,000 

June 

220,510 

19,030 

27,470 

—1,930 

530 

.3,010 

0 

323 

8.900 

July 

207,740 

19,030 

15,100 

—1,630 

0 

0 

0 

312 

4,720 

Aug. 

182,080 

18,410 

10,620 

—1,050 

0 

0 

0 

299 

3,280 

Sept. 

159,820 

19,030 

4,000 

—   400 

0 

0 

0 

287 

1,140 

Oct. 

144,180 

18,410 

0 

+    130 

0 

0 

0 

0 

Nov. 

136,600 

19,030 

0 

+   390 

0 

0 

0 

0 

Dec. 

Total  or 
average 

224,040 

235,780 

—6,300 

394,730 

61,000 

0 

300 

6,220 

176,760 

19,030 

44,710 

+   580 

23,440 

0 

0 

285 

12,770 

1923 

Jan. 

136,360 

17,190 

19,620 

+   420 

0 

0 

0 

275 

5,980 

Feb. 

133,270 

19,030 

46,120 

-1-   430 

0 

0 

0 

268 

12.340 

Mar. 

111,850 

18,410 

44,630 

—   370 

0 

0 

0 

282 

13,010 

April 

175,440 

19,030 

46,420 

—1,070 

113,000 

10,520 

0 

319 

14,790 

May 

210,400 

18,410 

44,760 

—1,460 

32,930 

0 

0 

321 

14,830 

June 

216,840 

19,030 

20,600 

—1,9.30 

0 

0 

0 

321 

6,670 

July 

203,780 

19,030 

9,100 

—1,550 

0 

0 

0 

3U 

2.840 

Aug. 

183,200 

18,410 

9,040 

—   990 

0 

0 

0 

301 

2,810 

Sept. 

163,800 

19,030 

3,000 

—   390 

0 

0 

0 

291 

870 

Oct. 

150,790 

18,410 

0 

+    120 

0 

0 

0 

0 

Nov. 

139,580 

19,030 

0 

+    350 

0 

0 

0 

0 

Dec. 
Total  nr 
average 

224,040 

288,000 

—5,860 

169,370 

10,520 

0 

297 

7,250 

127,850 

19,030 

8,670 

+   390 

0 

0 

0 

205 

2,300 

1924 

Jan. 

109,210 

17,800 

15,900 

-h   210 

0 

0 

0 

2.50 

4,250 

Feb. 

91,020 

19,030 

11,200 

+   200 

0 

0 

0 

235 

2,620 

Mar. 

72,790 

18,410 

30,000 

—    140 

0 

0 

0 

224 

6,940 

.\pril 

77,340 

19,0.30 

31,000 

—   420 

0 

0 

0 

243 

7,530 

May 

87,790 

18,410 

4,210 

—   640 

0 

0 

0 

231 

1,000 

June 

68,740 

19,030 

1,220 

—   690 

0 

0 

0 

210 

260 

Jaly 
.\u?. 

49,020 

19,030 

330 

—   450 

0 

0 

0 

183 

50 

29,540 

4,480 

2,980 

—   270 

0 

0 

13,930 

160 

490 

Sspt. 

24,790 

0 

5,340 

—    110 

0 

0 

19,030 

159 

850 

Got. 

24,089 

0 

18,200 

+     40 

0 

0 

18,410 

159 

2,990 

Niiv. 

24,720 

9,430 

10,950 

-f    120 

0 

0 

9,6J0 

159 

1,750 

Dec. 

163,680 

140,000 

—1,760 

0 

0 

60,970 

206 

2,570 

Total  or 
average 

310 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  6a  (Concluded).     PARDEE  RESER 

WATER  AND  POWER  YIELD  BOTH  WITH  AND  WITHOUT 

Monthly  Summary  of  Computa 
(For  corresponding  yearly  sum 

Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


Run-off 

Witliout  flood  control 

Power 

Year  and 

at 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

draft 

Average 

Average 
power 

yield  in 

kilowatts 
(Load 

facto  r= 
1.00) 

month 

Clements 

in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

through 
turbines 
including 
water 
passed 
for  prior 
rights  in 

Evapora- 
tion in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

power 

head 

through 

period 

of 

operation 

in  feet 

acre-feet 

1925 

Jan. 

22,500 

29,060 

19,030 

1,500 

-1-    160 

0 

0 

172 

260 

Feb. 

107,000 

31,190 

17,190 

2,500 

-1-   100 

0 

0 

231 

640 

Mar. 

81,800 

118,600 

19,030 

13,500 

+   260 

0 

0 

280 

3.780 

April 

164,000 

168,130 

18,410 

44,630 

—   290 

46,800 

0 

315 

14,530 

May 

237,000 

222,000 

19,030 

46,120 

—1,070 

170,780 

0 

325 

15,000 

June 

124,000 

222,000 

18,410 

44,630 

—1,460 

59,500 

0 

325 

15,000 

July 

21,000 

222,000 

19,030 

16,690 

—1,930 

0 

0 

322 

5,390 

Aug. 

10,200 

205,350 

19,030 

10,200 

—1,490 

0 

0 

312 

3,190 

Sept. 

7,910 

184,830 

18,410 

7,910 

—   990 

0 

0 

301 

2,470 

Oct. 

5,560 

165,430 

19,030 

3.000 

—   390 

0 

0 

291 

870 

Nov. 

7,620 

148,570 

18,410 

0 

+    130 

0 

0 

0 

Drc. 
Total  or 
average 

14,400 

137,910 

19,030 

0 

+    360 

0 

0 

0 

802,990 

224,040 

190,680 

—6,610 

277.080 

0 

288 

5.100 

Total  for 

21-year 

period 

1905-1926 

17.355.000 

4,649,250 

5.331.950 

122,650 

7,283,370 

58.640 

Average 

for 

21-year 

period, 

1905-1926 

826,430 

221,390 

253,900 

5,840 

345,870 

2.790 

296 

6,640 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS.  311 

VOIR  ON  MOKELUMNE  RIVER. 

FLOOD  CONTROL  BY  RESERVOIR  OPERATING  DIAGRAM, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  6,  page  124.) 

Yield  in  municipal  supply  200  million  gallons  daily. 
Installed  capacity  of  power  plant  15,000  k.w. 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Clements— rain-water  floods,  5,300  sec.-fi.;  snow-water  floods,  7,100  sec.-ft. 
Maximum  reservoir  space  required — rain-water  floods,  92,000  ac.-ft.;  snow-water  floods,  13,000  ac.-ft. 

Stage  of 
reservoir 

at  _ 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

Power 

draft 

through 

turbines 

including 

water 

passed 

for  prior 

rights  in 

acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 

over 
spillway 

in 
acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor^ 
1.00) 

Year  and 
month 

29,060 
31,190 
118,600 
168,130 
222,000 
211,490 
216,910 
200,640 
180,120 
160,720 
143,860 
133,200 

19,030 
17,190 
19,030 
18,410 
19.030 
18,410 
19,030 
19,030 
18,410 
19,030 
18,410 
19,030 

1,500 

2,500 

13,500 

44,680 

46,380 

43,870 

16,310 

10,200 

7,910 

3,000 

0 

0 

-f   160 
+    100 
-f    260 

—  290 
—1,070 
—1,460 
—1,930 
—1,490 

—  990 

—  390 
+    130 
+   360 

0 
0 
0 

19,410 
108,600 

54,840 
0 
0 
0 
0 
0 
0 

0 
0 
0 
27,340 
72,430 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

172 
231 
280 
315 
323 
321 
320 
310 
298 
288 

260 

640 

3,780 

14,530 

15,000 

14.540 

5,230 

3,160 

2,440 

860 

0 

0 

1925 

Jan. 

Feb. 
Mar. 

.April 

May 

June 

July 

Aug. 

Sept. 

Oct. 

Nov. 

Dec. 
Total  or 
average 

Total  for 
21-year 
period, 
1905-1926 

Average 

for 

21 -year 

period, 

1905-1926 

224,040 
4,646,920 

221,280 

189,850 
5,358,630 

255,170 

—6,610 
122.650 

5,840 

182,850 
5,145.700 

245,030 

99,770 
2,098,030 

99,910 

0 
60,970 

2.900 

286 
292 

5,040 
6,510 

312 


WATER  RESOURCES  OP   CALIFORNIA. 


TABLE  7a.     PARDEE  RESER 

COMPARISON  OF  WATER  AND  POWER  YIELD 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


Flood  control  by 

reservoir  operating  diagram 

Maximum  controlled  flow  at  Clements — rain-water  floods,  5,300 

sec.-ft.; 

snow-water  floods,  7,100  eec.-ft. 

Maximum  reservoir  space  required — rain-water  floods,  92,000  ac.-ft.; 

Run-oB 

snow-water  floods.  13,000  ac.-ft. 

at 

Power 

Year  and 
month 

Clements 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

draft 
through 
turbines 
including 
water 
passed 
for  prior 
rights  in 
acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets 

in 
acre-feet 

Waste 
over 

spillway 
in 

acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield:in 

kilowatts 
(Load 

factor= 
1.00) 

1905 

Jan. 

26,320 

145,860 

19,030 

10,500 

+   610 

0 

0 

0 

282 

2.960 

Feb. 

47,370 

143,260 

17,190 

22,500 

+   380 

0 

0 

0 

285 

7.100 

Mar. 

86,700 

151,320 

19,030 

46,120 

+   430 

0 

0 

0 

290 

13.370 

April 

116,600 

173,300 

18,410 

44,630 

-   370 

0 

4.490 

0 

311 

14,380 

May 

156,600 

222,000 

19,030 

46,200 

—1,070 

73,570 

21,890 

0 

324 

15,000 

June 

99,070 

216,840 

18,410 

40,510 

—1,460 

38,270 

0 

0 

323 

13.540 

July 

11,560 

217,260 

19,030 

11,560 

—1,930 

0 

0 

0 

318 

3.680 

Aug. 

7,870 

196,300 

19,030 

7,870 

—1,550 

0 

0 

0 

307 

2,420 

Sept. 

8,270 

175,720 

18,410 

8,270 

—    990 

0 

0 

0 

296 

2,530 

Oct. 

7,010 

156,320 

19,030 

3,000 

-   390 

0 

0 

0 

285 

860 

Nov. 

4,730 

140,910 

18,410 

0 

+    120 

0 

0 

0 

0 

Dec. 
Total  or 

5,960 

127,350 

19,0.30 

0 

-f   360 

0 

0 

0 

0 

average 

578,060 

224,040 

241,160 

-5,860 

111,840 

26,380 

0 

302 

6,300 

1906 
Jan. 

61,200 

114,640 

19,030 

0 

-f   420 

0 

0 

0 

0 

Feb. 

44,900 

157,230 

17.190 

41,650 

+   320 

0 

0 

0 

282 

13,020 

Mar. 

155,000 

143,610 

19,030 

44.580 

-t-   370 

63,140 

0 

0 

289 

12,880 

April 

175,000 

172,230 

18,410 

43,760 

—  370 

26,850 

35,840 

0 

314 

14.220 

May 

289,000 

222,000 

19,030 

46,430 

—1,070 

137.510 

96,860 

0 

323 

15.000 

June 

358,000 

210,100 

18,410 

45,110 

—1,460 

285,980 

0 

0 

322 

15.000 

July 

218,000 

217,140 

19.030 

44,620 

—1,930 

48,070 

99,620 

0 

325 

14,500 

Aug. 

21,900 

221,870 

19,030 

31,900 

—1,720 

0 

0 

0 

317 

10,130 

Sept. 

12,000 

191.120 

18,410 

11,600 

—1.110 

0 

0 

0 

305 

3,650 

Oct. 

11,700 

172,000 

19,030 

6,500 

—   410 

0 

0 

0 

296 

1,920 

Nov. 

14,800 

157,760 

18,410 

3,000 

+    140 

0 

0 

0 

289 

900 

Dec. 
Total  or 

53,900 

151,290 

19,030 

11.310 

+   420 

9,600 

0 

0 

292 

3,370 

average 

1,415,400 

224,040 

330,460 

-6.400 

571,150 

232,320 

0 

305 

8,680 

1907 

Jan. 

70,100 

165,670 

19.030 

49.580 

-f   630 

33,160 

0 

0 

283 

14.050 

Feb. 

154,000 

134,630 

17.190 

49.240 

+  420 

91,070 

0 

0 

275 

15,000 

Mar. 

300,000 

131,5,50 

19.030 

51.000 

-f   430 

149,290 

0 

0 

294 

14,950 

April 

264,000 

212,060 

18.410 

45.470 

—   370 

128,450 

61,960 

0 

319 

15,000 

May 

259,000 

222,000 

19.030 

46,120 

—1,070 

11,670 

181.110 

0 

325 

15,000 

June 

281,000 

222,000 

18.410 

44,630 

—1,460 

107,620 

108.880 

0 

325 

15.000 

July 

205,000 

222,000 

19,030 

46,120 

—1.930 

0 

137.920 

0 

325 

15.000 

Aug. 

43.200 

222,000 

19,030 

31.290 

-1.720 

0 

2.700 

0 

323 

10.130 

Sept. 

15,300 

210,460 

18,410 

30.500 

—1.230 

0 

0 

0 

311 

9.810 

Oct. 

17.000 

17.'5,620 

19,030 

9.500 

—  490 

0 

0 

0 

299 

2,840 

Nov. 

13,900 

163,600 

18.410 

9.000 

-1-    160 

0 

0 

0 

290 

2,710 

Dec. 
Total  or 

20,200 

150,250 

19.030 

3,000 

-f   480 

0 

0 

0 

286 

860 

average 

1,642,700 

224,040 

416.450 

—6,150 

521,260 

492.570 

0 

305 

10,820 

1908 

Jan. 

33.000 

148.900 

19,030 

12,500 

-f   610 

0 

0 

0 

286 

3,580 

Feb. 

22,600 

150,980 

17,800 

28.500 

+  400 

0 

0 

0 

279 

8,510 

Mar. 

60.200 

127,680 

19.030 

33,470 

+   430 

0 

0 

0 

302 

10.090 

April 
May 

103,000 

12.5,810 

18.410 

44,630 

—  370 

0 

0 

0 

277 

12.780 

117,000 

165.400 

19.030 

40,120 

-1.070 

0 

0 

0 

310 

14.300 

June 

75.000 

216.180 

18.410 

40,220 

—1,460 

0 

10,770 

0 

325 

13.600 

July 

14.100 

220.320 

19.030 

14,100 

—1,930 

0 

0 

0 

319 

4,500 

Aug. 

6.400 

199,360 

19.030 

0,400 

—1,550 

0 

0 

0 

309 

l,f89 

Sept. 

8.030 

178,780 

18.410 

8,030 

—   990 

0 

0 

0 

297 

2,470 

Oct 

8,730 

159,380 

19.030 

3,000 

—   390 

0 

0 

0 

288 

860 

Nov. 

7,380 

145,690 

18.410 

0 

+    130 

0 

0 

0 

0 

Dec 

Total  or 

9,900 

134,790 

19.030 

0 

+   370 

0 

0 

0 

0 

average 

455.340 

224,660 

230,970 

—6,820 

0 

10.770 

0 

299 

6,020 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 
VOIR  ON  MOKELUMNE  RIVER. 


313 


FOR  TWO  METHODS  OF  FLOOD  CONTROL, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  7,  page  12o.) 

Yield  in  municipal  supply  200  million  gallons  daily. 
Installed  capacity  of  power  plant  15,000  k.w. 


Flood  control, 

holding  maximum  reservoir  space  required  (rain- 

water  floods 

92.000  ac.-f 

f-; 

snow-water  floods,  13,000  ac.-ft.)  In  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Clements — rain- 

water  floods 

5,300  sec.-f 

.;  snow-water  floods,  7,100  sec.-f t. 

Power 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

draft 
through 
turbines 
including 

water 
passed 
for  prior 
rights  in 
acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

Year  and 
month 

1905 

101,560 

19,030 

10,500 

+    610 

0 

0 

0 

251 

2,630 

Jan. 

98,960 

17,190 

22,500 

+    380 

0 

0 

0 

254 

6,320 

Feb. 

107,020 

19,030 

46,120 

+   430 

0 

0 

0 

260 

12,020 

Mar. 

129,000 

18,410 

45,140 

—   370 

21,270 

0 

0 

275 

12,810 

April 

160,410 

19,030 

38,010 

—1,070 

49,900 

0 

0 

310 

11,870 

May 

209,000 

18,410 

41,550 

—1,460 

40,370 

0 

0 

319 

13,720 

June 

200,280 

19,030 

11,560 

—1,930 

0 

0 

0 

312 

3,620 

July 

185,320 

19,030 

7,870 

—1,550 

0 

0 

0 

301 

2,370 

Aug. 

164,740 

18,410 

8,270 

—   990 

0 

0 

0 

289 

2,470 

Sept. 

145,340 

19,030 

3,000 

—   390 

0 

0 

0 

278 

830 

Oct. 

129,930 

18,410 

0 

-f    120 

0 

0 

0 

0 

Nov. 

116,370 

19,030 

0 

+   360 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

234,520 

—5,860 

111,540 

0 

0 

285 

5,700 

1906 

103.660 

19.030 

10,200 

+   420 

6,050 

0 

0 

273 

2,770 

Jan. 

130,000 

17,190 

41,650 

+    320 

0 

0 

0 

263 

12,160 

Feb. 

116,380 

19,030 

50.920 

+    370 

67,620 

0 

0 

269 

13,700 

Mar. 

134,180 

18,410 

41,080 

—   370 

68,360 

0 

0 

279 

11,720 

April 

180,960 

19,030 

41,780 

—1,070 

149,080 

50,000 

0 

319 

13,370 

May 

209,000 

18,410 

45,380 

—1,460 

292,750 

0 

0 

320 

15,000 

June 

209,000 

19,030 

44,140 

—1,930 

41,760 

98,270 

0 

324 

14,310 

July 

221,870 

19,030 

31,900 

—1,720 

0 

0 

0 

317 

10,130 

Aug. 

191,120 

18,410 

11,600 

—1,110 

0 

0 

0 

305 

3,650 

Sept. 

172.000 

19,030 

6,500 

—   410 

0 

0 

0 

296 

1,920 

Oct. 

157,760 

18,410 

7,870 

+    140 

19,330 

0 

0 

282 

2,250 

Nov. 

127,090 

19,030 

19,950 

+   420 

12,430 

0 

0 

272 

5,390 

Dec. 
Total  or 
average 

224,040 

352,970 

—6,400 

657,380 

148,270 

0 

295 

8,850 

1907 

130,000 

19,030 

47,260 

-f    630 

4,440 

0 

0 

271 

12,820 

Jan. 

130,000 

17,190 

49,500 

-t-    420 

87,730 

0 

0 

274 

15,000 

Feb. 

130,000 

19,0.30 

52,200 

-f   430 

166,630 

0 

0 

288 

15,000 

Mar. 

192,570 

18.410 

38,470 

—   370 

180,090 

0 

0 

298 

11,780 

.\pril 

219,230 

19,030 

46,670 

—1,070 

155,220 

47,240 

0 

321 

15,000 

May 

209,000 

18,410 

45,460 

—1,460 

215,670 

0 

0 

319 

15,000 

June 

209,000 

19,030 

45,650 

—1,930 

31,150 

94,240 

0 

324 

14,810 

July 

222,000 

19,030 

31,290 

—1.720 

2,700 

0 

0 

323 

10,130 

Aug. 

210,460 

18,410 

30,500 

—1,230 

0 

0 

0 

311 

9,810 

Sept. 

175,620 

19,030 

9,500 

—   490 

0 

0 

0 

299 

2,840 

Oct. 

163,600 

18,410 

13,260 

+    160 

21,130 

0 

0 

283 

3,900 

Nov. 

124,860 

19,030 

3,000 

+   480 

0 

0 

0 

268 

810 

Dec. 

1 
i 

224,040 

412,760 

—6,150 

864,760 

141,480 

0 

298 

10,560 

Total  or 
average 

19C8 

123,510 

19,030 

12,500 

+    610 

0 

0 

0 

268 

3,350 

Jan. 

125,590 

17,800 

28,500 

+   400 

0 

0 

0 

261 

7,960 

Feb. 

102,290 

19,030 

33,470 

-f    430 

0 

0 

0 

252 

8,410 

Mar. 

100,420 

18,410 

39,750 

—   370 

0 

0 

0 

260 

10,670 

April 

144,890 

19,030 

31,510 

—1,070 

1,280 

0 

0 

303 

9,560 

May 

209,000 

18,410 

40,620 

—1,460 

16,180 

0 

0 

319 

13,420 

June 

207,330 

19,030 

14,100 

—1,9.30 

0 

0 

0 

313 

4,410 

July 

186,370 

19,030 

0,400 

-1,550 

0 

0 

0 

302 

1,940 

Aug 

165,790 

18,410 

8,030 

—   990 

0 

0 

0 

290 

2,400 

Sept. 

146,390 

19,0.30 

3,000 

-    390 

0 

0 

0 

280 

830 

Oct. 

132,700 

18,410 

0 

+    130 

0 

0 

0 

0 

Nov. 

121,800 

19.030 

0 

+   370 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,650 

217,880 

—5,820 

17,460 

0 

0 

285 

5,220 

20—52411 

314 


WATER  RESOURCES  OF   CALIFORNIA. 


Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


TABLE  7a  (Continued).     PARDEE 

COMPARISON  OF  WATER  AND  POWER  YIELD 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Flood  control  by 

reservoir  operating  diagram 

Maximum  controlled  flow  at  Clements— rain-water  fl 

3ods,  5,300 

sec.-ft.; 

snow-water  iloods,  7,100  sec.-ft. 

Maximum  reservoir  space  required — rain-water  floods,  92,000  ac.-ft.; 

Run-ofI 

snow-water  floods.  13,000  ac.-ft. 

at 

Power 

Year  and 
month 

Clements 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

draft 
through 
turbines 
including 
water 
passed 
for  prior 
rights  in 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets 

in 
acre-feet 

Waste 
over 

spillway 
in 

acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

.Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 

power 
■i-ieldMn 
kilowatts 

(Load 
factor=: 

1.00) 

acre-feet 

1909 

Jan. 

170,000 

120,030 

19,030 

20,990 

-f    440 

105,260 

0 

0 

294 

6,530 

Feb. 

126,000 

160,190 

17,190 

48,870 

+   420 

87,310 

0 

0 

277 

15,000 

Mar. 

103,000 

133,240 

19,030 

42,020 

-1-   430 

13,700 

0 

0 

282 

11,770 

April 

167,000 

161,920 

18,410 

35,940 

—   370 

12,220 

39,980 

0 

313 

11.750 

May 

228.000 

222,000 

19,030 

46,430 

—1,070 

99,300 

74,470 

0 

323 

lo.OOO 

June 

256,000 

209,700 

18,410 

45,270 

—1,460 

184,310 

0 

0 

321 

15.000 

July 

50,700 

216,250 

19,030 

30,130 

—1,930 

4,150 

0 

0 

324 

9.770 

Aug. 

7,070 

211,710 

19,030 

17,070 

—1,720 

0 

0 

0 

313 

5.350 

Sept. 

4,600 

180,960 

18,410 

7,600 

—1,110 

0 

0 

0 

298 

2,350 

Oct. 

8,060 

158,440 

19,030 

4.000 

—   410 

0 

0 

0 

287 

1.140 

Nov. 

56,600 

143,060 

18,410 

0 

-1-    140 

0 

0 

0 

0 

Dec. 
Total  or 
average 

92,200 

181,390 

19.030 

47.500 

+   480 

46.730 

0 

0 

312 

14,800 

1,278,230 

224.040 

345.820 

-6,160 

552.980 

114,450 

0 

304 

9,010 

1910 

Jan. 

82,400 

160,810 

19,030 

45,580 

+   680 

44,650 

0 

0 

286 

13,170 

Feb. 

52,600 

134,630 

17,190 

32,330 

+   420 

3,400 

0 

0 

275 

9,850 

Mar. 

117,000 

134,730 

19,030 

47,610 

-i-   430 

47,070 

0 

0 

287 

13,640 

April 

193,000 

168,450 

18,410 

42,440 

—   370 

22,500 

55,670 

0 

315 

13,860 

May 

196,000 

222,000 

19.030 

46,380 

—1,070 

92,040 

47,990 

0 

323 

15,000 

June 

59,500 

211,490 

18.410 

33,310 

—1,460 

14,690 

0 

0 

319 

10,920 

Jjly 

10,600 

203,120 

19,030 

10,600 

—1,930 

0 

0 

0 

310 

3,290 

Aug. 

3,960 

182,160 

19,030 

3,9P0 

—1,550 

0 

0 

0 

299 

1,180 

Sept. 

4,420 

161,580 

18,410 

4,420 

—   990 

0 

0 

0 

287 

1,310 

Oct. 

6,580 

142,180 

19,030 

3,000 

—   390 

0 

0 

0 

276 

820 

Nov. 

10,100 

126,340 

18,410 

0 

-f    120 

0 

0 

0 

0 

Dec. 
Total  or 
average 

21,900 

118,150 

19,030 

0 

+   370 

0 

0 

0 

0 

788,060 

224,040 

269,630 

—5,740 

224,410 

103,660 

0 

298 

6,900 

1911 

Jan. 

148,000 

121,390 

19,030 

18,120 

-f   470 

52,820 

0 

0 

275 

5,090 

Feb. 

143,000 

179,890 

17,190 

47,070 

+   420 

125,410 

0 

0 

286 

14,910 

Mar. 

204,000 

133,640 

19,030 

52,540 

-f    430 

102,620 

0 

0 

286 

15,000 

April 
May 

256.000 

103,880 

18,410 

46,240 

—   370 

78.010 

54,850 

0 

314 

15.000 

202,000 

222,000 

19,030 

46,160 

—1,070 

97,820 

103,280 

0 

325 

15.000 

June 

331,000 

216,640 

18,410 

44,870 

—1,460 

262,490 

0 

0 

323 

15,000 

July 

117,000 

220,410 

19,030 

40,400 

—1,930 

11,260 

47.420 

0 

325 

13,130 

Aug. 

16,500 

217,370 

19,030 

26,500 

-1,720 

0 

0 

0 

315 

8,360 

Sept. 

9,280 

186,620 

18,410 

11,500 

—1,110 

0 

0 

0 

302 

3,580 

Oct. 

8,790 

104,880 

19,030 

4,000 

—   410 

0 

0 

0 

290 

1,170 

Nov. 

11,900 

150,230 

18,410 

0 

+    140 

0 

0 

0 

0 

Dec. 
Total  or 
average 

8.300 

143,860 

19.030 

2,000 

-f-   400 

0 

0 

0 

278 

550 

1,615.830 

224.040 

339.400 

—6,210 

730,430 

205,550 

0 

302 

8,850 

1912 

Jan. 

14,000 

131,590 

19.030 

2,920 

+   490 

0 

0 

0 

272 

790 

Feb. 

10,800 

124,130 

17.800 

8,000 

+   300 

0 

0 

0 

263 

2,200 

Mar. 

21,000 

109,430 

19,030 

24,000 

+   290 

0 

0 

0 

249 

5.980 

April 

30,800 

87,690 

18,410 

34,000 

—  230 

0 

0 

0 

229 

8,040 

May 

140,000 

65.850 

19,030 

31,000 

—   600 

0 

0 

0 

247 

7.650 

June 

125,000 

155,220 

18,410 

33,020 

—1,250 

0 

10.360 

0 

319 

10,920 

July 

9,900 

217.180 

19,030 

9,900 

—1,930 

0 

0 

0 

318 

3,150 

Aug. 

6,580 

196.220 

19,030 

5,580 

—1,550 

0 

0 

0 

307 

1,720 

Sept. 

6.800 

176,640 

18,410 

6,600 

—   990 

0 

0 

0 

296 

2,010 

Oct. 

6.260 

156,240 

19,030 

3,000 

—   390 

0 

0 

0 

285 

860 

Nov. 

31.100 

130,080 

18,410 

0 

+    120 

0 

0 

0 

0 

Dec. 
Total  or 

10.600 

161,800 

19.030 

11,000 

+   400 

0 

0 

0 

28i 

3,090 

average 

410,640 

224.650 

169,020 

-6.340 

0 

10.360 

0 

279 

3,870 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 
RESERVOIR  ON  MOKELUMNE  RIVER. 


315 


FOR  TWO  METHODS  OF  FLOOD  CONTROL, 
tions  Carried  out  on  a  Daily  Basis. 
mary,  see  Table  7,  page  1 26.) 

Yield  in  municipal  supply  200  million  gallons  daily. 
Installed  capacity  of  power  plant  15,000  k.w. 


Flood  ccntrol. 

holding  maximum  reservoir  space  reiuired  (rain- 

Aafer  floods 

92,000  ac-ft.: 

snow-water  floods,  13,000  a 

\-ft.)  in  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Clements — rain- 

water  floods 

,  5,300  sec.-f 

.;  snow-water  floods.  7,100  sec.-f t. 

Power 

Stage  of 

draft 

Average 

reservoir 

through 

Release 

Deficiency 

power 

Average 

Year  and 

at_ 

Municipal 

turbines 

through 

Waste 

in 

head 

power 

month 

beginning 

draft 

including 

Evapora- 

flood 

over 

municipal 

through 

yield  in 

of  _ 

in 

water 

tion  in 

control 

spillway 

supply 

period 

kilowatts 

month  in 

acre-feet 

passed 

acre-feet 

outlets 

in 

in 

of 

(Load 

acre-feet 

for  prior 
rights  in 
acre-feet 

in 
acre-feet 

acre-feet 

acre-feet 

operation 
in  feet 

factor= 
1.00) 

1909 

113,040 

19,030 

32,070 

-f   440 

111,380 

0 

0 

271 

8,880 

.)an. 

130,000 

17,190 

49,590 

+   420 

59,640 

0 

0 

273 

15,000 

Feb. 

130,000 

19,030 

54,910 

+   430 

29,490 

0 

0 

273 

15,000 

Mar. 

130,000 

18,410 

42,370 

—   370 

53,940 

0 

0 

278 

12,060 

April 

181,910 

19,030 

44,230 

—1,070 

104,550 

32,030 

0 

319 

14,150 

May 

209,000 

18,410 

45,460 

—1,460 

190.670 

0 

0 

319 

15,000 

June 

209,000 

19,030 

28,190 

—1,930 

7,700 

0 

0 

320 

9,050 

July 

202,850 

19,030 

8,210 

—1,720 

0 

0 

0 

310 

2,550 

Aug. 

180.960 

18,410 

7,600 

—1,110 

0 

0 

0 

298 

2,350 

Sept. 

158,440 

19,030 

4,000 

—   410 

0 

0 

0 

287 

1,140 

Oct. 

143,060 

18,410 

19,400 

+    140 

31,990 

0 

0 

273 

5.490 

Nov. 

130,000 

19,030 

50,140 

-t-    480 

28,610 

0 

0 

272 

13,660 

Dec. 

Total  or 
average 

224,040 

386,170 

—6,160 

617,970 

32,030 

0 

292 

9,490 

1910 

124,900 

19,030 

50,310 

-1-  680 

8,640 

0 

0 

273 

13,710 

Jan. 

130,000 

17,190 

41,960 

+   420 

0 

0 

0 

271 

12,600 

Feb 

123,870 

19,030 

53,490 

+   430 

68,780 

0 

0 

273 

14,600 

Mar. 

130,000 

18,410 

45,420 

—   370 

63,120 

0 

0 

280 

13,030 

April 

195,680 

19.030 

43,250 

—1,070 

100,960 

18,370 

0 

320 

13,840 

May 

209,000 

18,410 

33,660 

—1,460 

14,.330 

0 

0 

318 

11,110 

June 

200,640 

19,030 

10,600 

—1,930 

0 

0 

0 

310 

3,280 

July 

179,680 

19,030 

3,960 

—1.550 

0 

0 

0 

298 

1,180 

Aug. 

159,100 

18,410 

4,420 

—    990 

0 

0 

0 

286 

1,310 

Sept. 

139,700 

19,030 

3,000 

—   390 

0 

0 

0 

274 

820 

Oct. 

123,860 

18,410 

0 

-f    120 

0 

0 

0 

0 

Nov. 

115,670 

19,030 

0 

+   370 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

290,070 

-5,740 

255,830 

18,370 

0 

290 

7,090 

1911 

118,910 

19,030 

27,530 

-f    470 

47,150 

0 

0 

270 

7,470 

Jan. 

173,670 

17,190 

48,110 

+   420 

121,790 

0 

0 

281 

14,960 

Feb. 

130,000 

19,030 

54,840 

+   430 

130,560 

0 

0 

273 

15,000 

Mar. 

130,000 

18,410 

41,070 

—   370 

126,840 

0 

0 

280 

11,740 

April 

199,310 

19,030 

43,940 

—1,070 

149,710 

38,560 

0 

320 

14,090 

.May 

209,000 

18,410 

45,450 

—1.460 

265,680 

0 

0 

319 

15,000 

,Iuiic 

209,000 

19,030 

,•^9,050 

—1,930 

22,400 

26,220 

0 

324 

12,620 

July 

217,370 

19,030 

26,500 

—1,720 

0 

0 

0 

315 

8,360 

Aug. 

180,620 

18,410 

11,500 

-1,110 

0 

0 

0 

302 

3,580 

Sept. 

164,880 

19,030 

4,000 

—   410 

0 

0 

0 

290 

1,170 

Oct. 

150,230 

18,410 

3,490 

+    140 

12,900 

0 

0 

278 

1,000 

Nov. 

127,470 

19,030 

2,000 

+   400 

0 

0 

0 

265 

540 

Dec. 
Total  or 
average 

224,040 

347,480 

—6,210 

877.030 

64,780 

0 

295 

8,750 

1912 

115,200 

19,030 

2,920 

+   490 

0 

0 

0 

260 

750 

Jan. 

107,740 

17.800 

8,000 

+   300 

0 

0 

0 

251 

2,140 

Feb. 

93,040 

19,030 

24.000 

+   290 

0 

0 

0 

234 

5,630 

Mar. 

71,300 

18,410 

32,670 

—   230 

0 

0 

0 

212 

7,170 

April 

50,790 

19,030 

31,000 

—    600 

0 

0 

0 

232 

7,190 

May 

140,160 

18,410 

32,740 

—1,250 

8,580 

0 

0 

312 

10,600 

June 

204,180 

19,030 

9,900 

—1,930 

0 

0 

0 

312 

3,080 

July 

183,220 

19.030 

5,580 

—1,550 

0 

0 

0 

300 

1,680 

Aug. 

162,640 

18,410 

6,600 

—   990 

0 

0 

0 

288 

1,960 

Sept. 

143,240 

19,030 

3,000 

—   390 

0 

0 

0 

276 

830 

Oct. 

126,080 

18.410 

J, 810 

+    120 

8,900 

0 

0 

275 

510 

Nov. 

128.180 

19,030 

11,000 

-t-   400 

0 

0 

0 

265 

2,920 

Dec. 
Total  or 
average 

224,650 

169,220 

—5,340 

17,480 

0 

0 

267 

3.700 

316 


WATER  RESOURCES  OF  CALIFORNIA. 


TABLE  7a  (Continued).     PARDEE 

COMPARISON  OF  WATER  AND  POWER  YIELD 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


Flood  control  L-y 

reservoir  operating  diat-ram 

Maximum  controlled  flow  at  Clements — rain-water  floods,  5.300 

sec.-ft.; 

snow-water  floods,  7.100  sec.-ft. 

Maximum  reservoir  space  required— rain-water  floods,  92,000 

ic.-ft.; 

Run-off 

snow-water  floods,  13  000  ac.-ft. 

at 

Power 

Year  and 
month 

Clements 

in 
acre-feet 

Stage  of 
reservoir 

at_ 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

draft 
through 
turbines 
including 
water 
passed 
for  prior 
rights  in 
acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets 

in 
acre-feet 

Waste 
over 

spillway 
in 

acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feef 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield :in 

kilowatts 
(Load 

factor= 
1.00) 

1913 

Jan. 

22,600 

132,760 

19,030 

2,500 

-f   490 

0 

0 

0 

274 

690 

Feb. 

10,800 

134,320 

17,190 

18,500 

+    300 

•   0 

0 

0 

271 

5,540 

Mar. 

21,600 

118,730 

19,030 

34,770 

+   310 

0 

0 

0 

252 

8,760 

April 

83,000 

86,840 

18,410 

35.000 

—   260 

0 

0 

0 

247 

8,930 

May 

148,000 

117,070 

19,030 

32,060 

-   830 

0 

0 

0 

292 

9,370 

June 

55,300 

213,150 

18,410 

32,210 

—1,460 

0 

3,280 

0 

324 

10,790 

July 

10,500 

213,090 

19,030 

10,500 

—1,930 

0 

0 

0 

316 

3,320 

Aug. 

8,360 

192,130 

19,030 

8,360 

—1,550 

0 

0 

0 

305 

2,550 

Sept. 

6,370 

171,550 

18,410 

6,370 

—   990 

0 

0 

0 

293 

1,930 

Oct. 

7,130 

152,150 

19,030 

3,000 

—   390 

0 

0 

0 

282 

850 

Nov. 

8,090 

136,860 

18,410 

0 

+    130 

0 

0 

0 

0 

Dec. 
Total  or 

14,300 

126,670 

19,030 

0 

+   360 

0 

0 

0 

0 

average 

405,950 

224,040 

183,270 

—5,820 

0 

3,280 

0 

286 

4,370 

1914 
Jan. 

169,000 

122,300 

19,030 

39.510 

-f   450 

95,510 

0 

0 

283 

11,160 

Feb. 

102,000 

137,700 

17,190 

42,430 

+   420 

48,850 

0 

0 

275 

12,920 

Mar. 

105,000 

131,650 

19,030 

45.680 

+   430 

6,190 

0 

0 

283 

12,840 

April 

144,000 

166,180 

18,410 

39.980 

—   370 

17,370 

12,050 

0 

314 

13,060 

May 

261,000 

222,000 

19,030 

46,430 

—1.070 

152,780 

53,790 

0 

323 

15,000 

June 

198,000 

209,000 

18,410 

45,270 

—1,460 

126,510 

0 

0 

320 

15,000 

July 

50,200 

216,250 

19,030 

30,790 

—1,930 

1,900 

890 

0 

324 

10,130 

Aug. 

10,200 

211,910 

19,030 

20,200 

—1.720 

0 

0 

0 

313 

6,330 

Sept. 

7,800 

181,160 

18,410 

10.800 

—1,110 

0 

0 

0 

298 

3.330 

Oct. 

8,120 

158,640 

19,030 

7,000 

—   410 

0 

0 

t) 

286 

2,000 

Nov. 

7,970 

140,320 

18,410 

0 

+    140 

0 

0 

0 

0 

Dec. 
Total  or 

12,600 

130,020 

19,030 

0 

+   390 

0 

0 

0 

0 

average 

1,075,890 

224,040 

328,090 

—6,240 

449,110 

66,730 

0 

302 

8.450 

1915 
Jan. 

19,600 

123,980 

19,030 

1,500 

+   490 

0 

0 

0 

269 

400 

Feb. 

75,000 

123,540 

17,190 

22,210 

-i-   300 

17,270 

0 

0 

278 

6.860 

Mar. 

61,400 

142,170 

19,030 

18,950 

+   390 

1,190 

0 

0 

286 

5,4S0 

April 
May 

133,000 

164.790 

18,410 

44,630 

—   370 

12,380 

0 

0 

310 

14,310 

218,000 

222,000 

19,030 

46,410 

—1,070 

142,010 

20,690 

0 

323 

15.000 

June 

231,000 

210,790 

18,410 

45,230 

—1,460 

159.450 

0 

0 

321 

15.000 

July 

44,000 

217,240 

19,030 

28,130 

—1,930 

1.270 

340 

0 

323 

9,130 

Aug. 

5,710 

210,540 

19,030 

9,710 

—1,630 

0 

0 

0 

314 

3,050 

Sept. 

6,370 

185,880 

18,410 

9,370 

—1,050 

0 

0 

0 

300 

2,920 

Oct. 

6,830 

163,420 

19,030 

4,000 

—   400 

0 

0 

0 

289 

1.160 

Nov. 

8,690 

146,820 

18,410 

0 

+   130 

0 

0 

0 

0 

Dec. 
Total  or 

19,800 

137,230 

19,030 

0 

-f   390 

0 

0 

0 

0 

average 

829,400 

224,040 

230,140 

—6,210 

333.570 

21,030 

0 

302 

6.080 

1916 
Jan. 

79,300 

138,390 

19.030 

30.450 

-f   490 

34.170 

0 

0 

280 

8.510 

Feb. 

97,800 

134,530 

17.800 

49,270 

-f    400 

30,730 

0 

0 

275 

14,470 

Mar. 

176.000 

134.930 

19.030 

52.940 

+    430 

72,920 

0 

0 

283 

14,990 

April 
May 

195,000 

165.470 

18.410 

44.740 

—    370 

21.790 

53,160 

0 

314 

14,510 

205.000 

222,000 

19.030 

46.420 

—1,070 

77,790 

72,090 

0 

323 

15,000 

June 

181,000 

210.600 

18.410 

45.170 

—1.460 

109.520 

0 

0 

321 

14,970 

July 

46,900 

217,040 

19,030 

30,370 

—1.930 

0 

860 

0 

324 

9.850 

Aug. 

10,500 

211,750 

19.030 

19.500 

—1.720 

0 

0 

0 

313 

0,100 

Sept. 

0,720 

182,000 

18,410 

9.720 

—1,110 

0 

0 

0 

299 

3,000 

Oct. 

12,700 

159,480 

19,030 

6,000 

—   410 

0 

0 

0 

288 

1,730 

Nov. 

11,800 

146,740 

18.410 

4.000 

+    140 

0 

0 

0 

280 

1,170 

Dec. 
Total  or 

27,600 

136,270 

19.030 

1,000 

+    400 

0 

0 

0 

282 

280 

average 

1,049,320 

224,650 

339,580 

-6.210 

346.920 

126,110 

0 

298 

8,690 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 
RESERVOIR  ON  MOKELUMNE  RIVER. 


317 


FOR  TWO  METHODS  OF  FLOOD  CONTROL, 
tions  Carried  out  on  a  Daily  Basis. 

maty,  see  Table  7,  page  126.) 

Yield  in  municipal  supply  200  million  gallons  daily. 
Installed  capacity  of  power  plant  15,000  k.w. 


Flood  control 

holding  maximum  reservoir  space  required  (rain- 

water  floods 

92,000  ac- 

t.; 

snow-water  floods,  13,000  ac.-ft.)  in  reserve  throughout  flood  ses 

son 

Maximum  controlled  flow  at  Clements — rain-water  floods 

5,300  sec.-f 

.;  snow-water  floods,  7,100  sec.-f t. 

Power 

i 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

draft 
through 
turbines 
including 
water 
passed 
for  prior 
rights  in 
acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets 

in 
acre-feet 

I     Waste 
over 
spillway 

in 
acre-feet 

Deficiency 

in_ 

municipal 

supply 

in 
acre-feet 

.Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Lead 

factor= 
1.00) 

Year  and 

month 

1913 

109,050 

19,030 

2,500 

+   490 

0 

0 

0 

257 

650 

Jan. 

110,610 

17.190 

18,500 

+   300 

0 

0 

0 

252 

5,180 

Feb. 

95,020 

19,030 

34,770 

+   310 

0 

0 

0 

230 

8,010 

Mar. 

63,130 

18,410 

33,320 

—   260 

0 

0 

0 

225 

7,750 

April 

95,040 

19,030 

31,000 

—   830 

0 

0 

0 

278 

8,600 

May 

192,180 

18,410 

27,540 

—1,460 

0 

0 

0 

317 

9,040 

.Tune 

200,070 

19,030 

10,500 

—1,930 

0 

0 

0 

310 

3,250 

July 

179,110 

19,030 

8,360 

—1,550 

0 

0 

0 

298 

2,490 

.Aug. 

158,530 

18,410 

0,370 

—   990 

0 

0 

0 

285 

1,880 

Sept. 

139,130 

19.030 

3,000 

—   390 

0 

0 

0 

274 

820 

Oct. 

123,840 

18,410 

0 

+   130 

0 

0 

0 

0 

Nov. 

113,650 

19,030 

0 

+   360 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

175,860 

—5,820 

0 

0 

0 

273 

3,950 

109,280 

19,030 

43,920 

4-   450 

85,780 

0 

0 

273 

12,030 

1914 

Jan. 

130,000 

17,190 

45,280 

+   420 

39,950 

0 

0 

273 

13,660 

Feb. 

130,000 

19,030 

54,910 

+   430 

31,490 

0 

0 

273 

15,000 

Mar. 

130,000 

18,410 

40,340 

—   370 

60,080 

0 

0 

276 

11,440 

April 

154.800 

19,030 

41,000 

—1,070 

145,700 

0 

0 

313 

12,930 

May 

209,000 

18,410 

45,460 

—1,460 

132,670 

0 

0 

319 

15,000 

June 

209,000 

19,030 

28,500 

—1,930 

5,910 

0 

0 

320 

9,150 

July 

203,830 

19,030 

12,120 

—1,720 

0 

0 

0 

311 

3,760 

Aug. 

181,160 

18,410 

10,800 

—1,110 

0 

0 

0 

298 

3,330 

Sept. 

158,640 

19,030 

7,000 

—   410 

0 

0 

0 

286 

2,000 

Oct. 

140,320 

18,410 

1,760 

+    140 

3,360 

0 

0 

275 

500 

Nov. 

124,900 

19,030 

0 

+   390 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

331,090 

—6,240 

504,940 

0 

0 

294 

8.200 

1915 

118,860 

19,030 

1,500 

-1-   490 

0 

0 

0 

265 

400 

Jan. 

118,420 

17,190 

35,890 

+   300 

10,640 

0 

0 

273 

10,890 

Feb. 

130,000 

19,030 

46,120 

+   390 

0 

0 

0 

268 

12,370 

Mar. 

126,640 

18,410 

41,390 

—   370 

32,520 

0 

0 

277 

11,780 

April 

166,950 

19,030 

40,800 

—1,070 

115,050 

0 

0 

312 

12,810 

May 

209,000 

18.410 

45,460 

—1,460 

165,670 

0 

0 

319 

15,000 

Juno 

209,000 

19,030 

2.5,810 

—1,930 

4,020 

0 

0 

320 

8,280 

July 

202,210 

19,030 

5,710 

—1,630 

0 

0 

0 

310 

1.770 

Aug 

181,550 

18,410 

6,370 

—1,050 

0 

0 

0 

300 

1,970 

.Sept. 

162,090 

19,030 

3,000 

—   400 

0 

0 

0 

289 

860 

Oct. 

146,490 

18,410 

1,750 

+    130 

8,870 

0 

0 

276 

500 

Nov. 

126,280 

19,030 

0 

+   390 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

253,800 

-6,210 

336,770 

0 

0 

293 

6,340 

127,440 

19,030 

36,210 

-f-   490 

21,990 

0 

0 

273 

9,890 

1916 

Jan. 

130,000 

17,800 

50,520 

+   400 

29,880 

0 

0 

273 

14,740 

Feb. 

130,000 

19,030 

54,850 

+   430 

101,550 

0 

0 

273 

15,000 

Mar. 

130,000 

18,410 

41,100 

—   370 

70,650 

0 

0 

279 

11,720 

April 

194,470 

19,030 

44,720 

-1,070 

83,920 

41,730 

0 

320 

14,330 

.May 

209,000 

18,410 

45,460 

—1,460 

115,670 

0 

0 

319 

15,000 

June 

209,000 

19,030 

28,250 

—1,930 

1,690 

0 

0 

320 

9,090 

July 

205,000 

19,030 

12,750 

-1,720 

0 

0 

0 

312 

3,980 

.\ug. 

182,000 

18,410 

9,720 

—1,110 

0 

0 

0 

299 

3,000 

Sept. 

159,480 

19,030 

6,000 

—   410 

0 

0 

0 

288 

1,730 

Oct. 

146,740 

18,410 

5,620 

+    140 

8,880 

0 

0 

277 

1,710 

Nov. 

125,770 

19,030 

5,550 

+   400 

0 

0 

0 

272 

1,510 

Dec. 
Total  or 
average 

224,650 

340,750 

-6,210 

434,230 

41,730 

0 

292 

8.450 

318 


WATER   RESOURCES  OF   CALIFORNIA. 


TABLE  7a  (Continued).     PARDEE 

COMPARISON  OF  WATER  AND  POWER  YIELD 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


Flood  control  by 

reservoir  operating  diagram 

Maximum  controlled  flow  at  Clements — 

rain-water  floods,  5,300 

sec.-ft.; 

snow-water  floods,  7, 

100  sec.-ft. 

Maximum  reservoir  space  refiuired— rain-water  floods,  92,000 

ac.-ft.; 

Run-off 

snow-water  floods,  13,000  ac.-ft. 

at 

Power 

Year  and 
month 

Clements 

in 
aore-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

draft 
through 
turbines 
including 

water 

passed 

for  prior 

rights  in 

acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

'  municipal 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 

,     power 

yield  in 

lalowatts 

(Load 

factor= 

1.00) 

1917 

Jan. 

20,000 

144,240 

19,030 

19,500 

+   530 

0 

0 

0 

276 

5,390 

Feb. 

69,400 

126,240 

17.190 

17,750 

+   330 

13.790 

1               0 

0 

270 

5.360 

Mar. 

59,500 

147,240 

19,030 

28,180 

+  430 

1,900 

0 

0 

288 

8.150 

.\pril 

134.000 

158,060 

18,410 

44,630 

—   370 

0 

0,650 

0 

306 

14,100 

May 

207,000 

222,000 

19,030 

46,180 

—1,070 

59,840 

85,440 

0 

325 

15,000 

June 

264,000 

217,440 

18,410 

44,750 

—1,460 

187,820 

7,000 

0 

324 

15,000 

July 

47.000 

222,000 

19,030 

29,530 

—1,930 

0 

6,000 

0 

324 

9,580 

Aug. 

9,350 

212,510 

19.030 

16,350 

—1,720 

0 

0 

0 

314 

5,130 

Sept. 

5,680 

184,760 

18.410 

8,680 

—1,110 

0 

0 

0 

301 

2,690 

Oct. 

4.590 

162,240 

19,030 

4.000 

—   410 

0 

0 

0 

288 

1,160 

Nov. 

5,110 

143,390 

18,410 

0 

+   130 

0 

0 

0 

0 

Dec. 

3,230 

130,220 

19,030 

0 

+   390 

0 

0 

0 

0 

Total  or 
average 

828,860 

224.040 

259,550 

—6,260 

263,350 

105,090 

0 

302 

6,790 

1918 

Jan. 

3.170 

114.810 

19.030 

1,500 

-f   450 

0 

0 

0 

255 

380 

Feb. 

19.400 

97,900 

17.190 

9,760 

+   250 

0 

0 

0 

242 

2.620 

Mar. 

106,000 

90,600 

19,030 

15,000 

+    250 

0 

0 

0 

266 

3,990 

April 

122,000 

162,820 

18,410 

44,630 

—   300 

0 

0 

0 

306 

14,100 

May 

148,000 

221,480 

19.030 

46,120 

—1,070 

0 

81,260 

0 

325 

15,000 

June 

87,500 

222.000 

18,410 

37,660 

—1,460 

0 

35,420 

0 

325 

12,640 

July 

7,930 

216.550 

19,030 

7,930 

-1,930 

0 

0 

0 

317 

2,510 

Ang. 

4,860 

195.590 

19,030 

4.860 

—1,550 

0 

0 

0 

307 

1.490 

Sept. 

8,810 

175.010 

18,410 

8.810 

—   990 

0 

0 

0 

295 

2,680 

Oct. 

13,700 

155.610 

19,030 

3.000 

-   390 

0 

0 

0 

287 

860 

Nov. 

12,300 

146,890 

18.410 

0 

+    130 

0 

0 

0 

0 

Dec. 
Total  or 
average 

12,500 

140,910 

19.030 

0 

+   390 

0 

0 

0 

0 

546,170 

224,040 

179.270 

—6.220 

0 

116,680 

0 

293 

4,680 

1919 
Jan. 

10,300 

134,770 

19.030 

6.000 

-1-   470 

0 

0 

0 

271 

1,630 

Feb. 

47,100 

120,510 

17,190 

10.500 

+  280 

0 

0 

0 

272 

3,150 

Mar. 

51,500 

140.200 

19,030 

46,120 

+  310 

0 

0 

0 

273 

12,590 

April 
May 

146,000 

126.860 

18,410 

44,630 

-   280 

0 

0 

0 

291 

13,400 

247,000 

209.540 

19,030 

46,120 

-1.070 

0 

168,320 

0 

32,S 

15.000 

June 

33,800 

222.000 

18,410 

24,270 

—1,460 

0 

3,250 

0 

323 

8.130 

July 

5,560 

208.410 

19,030 

5,560 

—1,740 

0 

0 

0 

313 

1,750 

Aug. 

4,930 

187.640 

19.030 

4,930 

—1,380 

0 

0 

0 

303 

1,490 

Sept. 

5,180 

167.230 

18,410 

5,180 

—   930 

0 

0 

0 

291 

1,560 

Oct. 

4.690 

147.890 

19,030 

3,000 

-   360 

0 

0 

0 

279 

830 

Nov. 

5.270 

130.190 

18,410 

0 

-1-    120 

0 

0 

0 

0 

Dec. 
Total  or 

11,800 

117.170 

19,030 

0 

+   320 

0 

0 

0 

... 

0 

average 

673,130 

224,040 

196,310 

—5,720 

0 

171.570 

0 

294 

4.970 

1920 

Jan. 

7.810 

110.260 

19.030 

1.500 

-f-   390 

0 

0 

0 

254 

380 

Feb. 

8.230 

97,930 

17,800 

2.500 

-1-  230 

0 

o! 

0 

243 

foO 

Mar. 

43.600 

86.090 

19,030 

19.380 

+   220 

0 

0 

0 

241 

4.680 

April 
May 

88.700 

91.500 

18,410 

35.000 

—    190 

0 

0 

0 

252 

9.110 

191,000 

126.600 

19,030 

35,880 

—   720 

0 

39.970 

0 

304 

10,990 

June 

78,500 

222,000 

18,410 

38,240 

-1,460 

0 

24,370 

0 

325 

12,830 

July 

13,800 

218,020 

19,030 

13,800 

—1.930 

0 

0 

0 

318 

4.400 

Aug. 

5,840 

197,060 

19,030 

5,840 

—1.550 

0 

0 

0 

308 

1,800 

Sept. 

4,840 

176,480 

18,410 1 

4,840 

-   990 

0 

0 

0 

296 

1,490 

Oct. 

9.690 

157,080 

19,030 

3,000 

—   390 

0 

0 

0 

286 

860 

Nov. 

19.900 

144,250 

18.410 

0 

+    130 

0 

0 

0 

0 

Dec. 
Totftl  or 

34.600 

145.870 

19,030 

0 

+   390 

0 

0 

0 

0 

mirerage 

500.310 

224,650 

159,980 

-5.870 

0 

64.340 

0 

283 

3,930 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS.  319 

RESERVOIR  ON  MOKELUMNE  RIVER. 

FOR  TWO  METHODS  OF  FLOOD  CONTROL, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  7,  page  126.) 

Yield  in  municipal  supply  200  million  gallons  daily. 
Installed  capacity  of  power  plant  15,000  k.w. 


l-'lood  control,  holding  maximum  reservoir  space  required  (rain-water  floods,  92,000  ac.-ft 

snow-water  floods,  13,000  ac 

.-ft.)  In  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Clements— rain-water  floods,  5,300  sec.-ft 

;  snow-water  floods,  7,100  sec.-ft. 

Power 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

draft 
through 
turbines 
including 
water 
passed 
for  prior 
rights  in 
acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 
in 

municipal 
supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factors 
1.00) 

Year  and 
month 

1917 

129,190 

19,030 

19,500 

+   530 

0 

0 

0 

267 

5,200 

Jan. 

111,190 

17,190 

20,380 

+    330 

13,350 

0 

0 

258 

5,890 

Feb. 

130,000 

19,030 

46,440 

-1-   430 

180 

0 

0 

270 

12,580 

Mar. 

124,280 

18,410 

3S,1£0 

—   370 

19,860 

0 

0 

278 

10,880 

April 

181,450 

19,030 

42,770 

—1,070 

110,550 

6,030 

0 

318 

13,640 

May 

209,000 

18,410 

45,460 

—1,460 

198,670 

0 

0 

319 

15,000 

June 

209,000 

19,030 

26,260 

—1,930 

3,170 

0 

0 

321 

8,440 

July 

205,610 

19,030 

9,450 

—1,720 

0 

0 

0 

312 

2,960 

Aug. 

184,760 

18,410 

8,680 

-1,110 

0 

0 

0 

301 

2,690 

Sept. 

162,240 

19,030 

4,000 

—   410 

0 

0 

0 

288 

1,160 

Oct. 

143,390 

18,410 

1,760 

+   130 

4,530 

0 

0 

276 

500 

Nov. 

123,930 

19,030 

0 

-t-   390 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

262,890 

-6,260 

350,310 

6,030 

0 

293 

6,580 

1918 

108,520 

19,030 

1,500 

+   450 

0 

0 

0 

250 

380 

Jan. 

91,610 

17,190 

7,900 

+   250 

0 

0 

0 

238 

2,080 

Feb. 

86,170 

19,030 

30,900 

+   250 

12,490 

0 

0 

258 

8,240 

Mar. 

130,000 

18,410 

44,610 

—   300 

17,330 

0 

0 

278 

12,750 

April 

171,350 

19,030 

41,810 

—1,070 

48,440 

0 

0 

317 

13,290 

May 

209,000 

18,410 

38,060 

—1,460 

35,040 

0 

0 

319 

12,580 

June 

203,530 

19,030 

7,930 

—1,930 

0 

0 

0 

310 

2,460 

July 

182,570 

19,030 

4,860 

—1,550 

0 

0 

0 

300 

1,450 

Aug. 

161,990 

18,410 

8,810 

—   990 

0 

0 

0 

288 

2,610 

Sept. 

142,590 

19,030 

3,000 

—   390 

0 

0 

0 

278 

830 

Oct 

133,870 

18,410 

260 

-t-    130 

0 

0 

0 

273 

70 

Nov. 

127,630 

19,030 

0 

-1-    390 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

189,640 

—6,220 

113,300 

0 

0 

284 

4,730 

1919 

121,490 

19,030 

6,000 

-1-    470 

0 

0 

0 

262 

1,570 

Jan. 

107,230 

17,190 

10,500 

+    280 

0 

0 

0 

263 

3,050 

Feb. 

126,920 

19,030 

46,120 

+    310 

0 

0 

0 

264 

12,180 

Mar. 

113,.580 

18,410 

42,940 

—   280 

11,920 

0 

0 

278 

12,250 

April 

186,030 

19,030 

45,210 

—1,070 

119,760 

38,960 

0 

320 

14,490 

May 

209,000 

18,410 

24,430 

—1,460 

3,100 

0 

0 

317 

8,080 

June 

195,400 

19,030 

5,560 

—1,740 

0 

0 

0 

306 

1,710 

July 

174,630 

19,030 

4,930 

—1,380 

0 

0 

0 

295 

1,450 

Aug. 

154,220 

18,410 

5,180 

—   930 

0 

0 

0 

282 

1,510 

Sept. 

134,880 

19,030 

3,000 

—   360 

0 

0 

0 

270 

810 

Oct. 

117,180 

18,410 

0 

+    120 

0 

0 

0 

0 

Nov. 

104,160 

19,030 

0 

+   320 

0 

0 

0 

0 

Dec. 
Total  or 

224,040 

193,870 

—5.720 

134,780 

38,960 

0 

286 

4,760 

average 
1920 

97,250 

19,030 

1,500 

+    390 

0 

0 

0 

242 

300 

Jan. 

84,920 

17,800 

2,500 

+   230 

0 

0 

0 

232 

620 

Feb. 

73,080 

19,030 

19,380 

+   220 

0 

0 

0 

229 

4,440 

Mar. 

78,490 

18,410 

33,160 

—    190 

0 

0 

0 

241 

8,250 

April 

115,430 

19,030 

36,580 

—    720 

41,100 

0 

0 

290 

10,980 

May 

209,000 

18,410 

38,650 

—1.460 

23,650 

0 

0 

319 

12,760 

June 

205,330 

19,030 

13,800 

-1,930 

0 

0 

0 

312 

4,300 

July 

184,370 

19,030 

5,840 

-1,550 

0 

0 

0 

300 

1,760 

Aug. 

163,790 

18,410 

4,840 

—   990 

0 

0 

0 

289 

1,440 

Sept. 

144,390 

19,030 

3,000 

—   390 

0 

0 

0 

278 

830 

Oct. 

131,560 

18,410 

3,180 

+    130 

0 

0 

0 

273 

920 

Nov. 

130,000 

19,030 

14,990 

+   390 

870 

0 

0 

273 

4,090 

Dec. 
Total  or 

224,650 

177,420 

—5,870 

65,620 

0 

0 

274 

4,230 

average 

320 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  7a  (Continued).     PARDEE 

COMPARISON  OF  WATER  AND  POWER  YIELD 
Monthly  Summary  of  Computa 


Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


(For  corresponding  yearly  sum 


Flood  control  by 

reservoir  operating  diagram 

Maximum  controlled  flow  at  Clements — rain-water  floods,  5,300 

sec.-ft.; 

snow-water  floods.  7,100  sec.-ft. 

Maximum  reservoir  space  required— rain-water  floods,  92,000  ac.-ft.; 

Run-off 

snow-water  floods,  13,000  ac.-ft. 

Power 

Year  and 
month 

at 
Clements 

Stage  of 

draft 
through 

Eelease 

Waste 
over 

spillway 
in 

acre-feet 

Deficiency 

Average 
power 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

in 
acre-feet 

reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

turbines 
including 
water 
passed 
for  prior 
rights  in 

Evapora- 
tion in 
acre-feet 

through 

flood 

control 

outlets 

in 
acre-feet 

in 

municipal 

supply 

in 
acre-feet 

head 

through 

period 

of 

operation 

in  feet 

acre-feet 

1921 

Jan. 

78,700 

161,730 

19,030 

46,650 

-1-   530 

40,060 

0 

0 

283 

13,200 

Feb. 

61,100 

135,220 

17,190 

38,130 

+   420 

4,710 

0 

0 

275 

11,620 

Mar. 

108,000 

136,710 

19,030 

39,360 

+   430 

15,090 

0 

0 

287 

10,970 

April 

123,000 

171,660 

18,410 

32,610 

—   370 

21,270 

0 

0 

314 

10,400 

May 

218,000 

222,000 

19,030 

46,320 

—1,070 

105,650 

55,850 

0 

324 

15,000 

June 

178,000 

212,080 

18,410 

44,630 

—1,460 

106,950 

0 

0 

322 

14,850 

July 

20,400 

218,630 

19,030 

16.740 

-1,930 

0 

0 

0 

320 

5,420 

Aug. 

7,750 

201,330 

19,030 

7,750 

—1,550 

0 

0 

0 

310 

2,410 

Sept. 

5,710 

180,7.50 

18,410 

5,710 

—   990 

0 

0 

0 

299 

1,760 

Oct. 

7,190 

161,350 

19,030 

3,000 

-    390 

0 

0 

0 

288 

860 

Nov. 

4,530 

146,120 

18,410 

0 

+    130 

0 

0 

0 

0 

Dec. 
Total  or 
average 

10,900 

132,370 

19,030 

0 

+   360 

0 

0 

0 

0 

823.280 

224,040 

280,900 

-5,890 

293,730 

55,850 

0 

302 

7,170 

1922 

Jan. 

19,200 

124,600 

19,030 

1,500 

+  440 

0 

0 

0 

271 

400 

Feb. 

58,900 

123,710 

17,190 

8,450 

+   270 

5,650 

0 

0 

278 

2,650 

Mar. 

56,500 

151,590 

19,030 

32,800 

+    330 

0 

0 

0 

288 

9,790 

April 

107,000 

156,590 

18,410 

44,630 

-   320 

0 

0 

0 

297 

13,690 

May 

318,000 

200,230 

19,030 

46,270 

—1,070 

178,710 

57,990 

0 

323 

14,970 

June 

280,000 

21.5,160 

18,410 

44,940 

—1,460 

209,840 

0 

0 

323 

15,000 

July 

39,200 

220,510 

19,030 

27,470 

—1,930 

530 

3,010 

0 

323 

8,900 

Aug. 

10,100 

207,740 

19,030 

15,100 

—1,630 

0 

0 

0 

312 

4,720 

Sept. 

7,620 

182,080 

18,410 

10,620 

—1,050 

0 

0 

0 

299 

3.280 

Oct. 

7,990 

159,620 

19,030 

4,000 

—   400 

0 

0 

0 

287 

1,140 

Nov. 

10,700 

144,180 

18,410 

0 

-1-    130 

0 

0 

0 

0 

Dec. 
Total  or 
average 

58,800 

136,600 

19,030 

0 

+    390 

0 

0 

0 

0 

974,010 

224,040 

235,780 

—6,300 

394,730 

61,000 

0 

300 

6,220 

1923 

Jan. 

46,200 

176,760 

19,030 

44,710 

+   580 

23,440 

0 

0 

285 

12,770 

Feb. 

33,300 

136,360 

17,190 

19,260 

+   420 

0 

0 

0 

275 

5,980 

Mar. 

43,300 

133,270 

19,030 

46,120 

-1-    430 

0 

0 

0 

268 

12,340 

April 

127,000 

111,850 

18,410 

44,630 

—   370 

() 

0 

0 

282 

13,010 

May 

225,000 

175,440 

19,030 

46,420 

—1,070 

113,000 

10,520 

0 

319 

14,790 

June 

104,000 

210,400 

18,410 

44,760 

—1.460 

32,930 

0 

0 

321 

14,830 

July 

28.500 

216,840 

19,030 

20,600 

—1,930 

0 

0 

n 

.321 

6,670 

Aug. 

9,100 

203,780 

19,030 

9,100 

-1,550 

0 

0 

0 

311 

2,840 

Sept. 

9,040 

183,200 

18,410 

9,040 

—   990 

0 

0 

0 

301 

2,810 

Oct. 

9,410 

163.800 

19,030 

3,000 

—   390 

0 

0 

0 

291 

870 

Nov. 

7,080 

150,790 

18,410 

0 

+    120 

0 

0 

0 

0 

Dec. 
Total  or 
average 

6.950 

139,580 

19,030 

0 

+    350 

0 

0 

0 

0 

648,880 

224,040 

288,000 

-5,860 

169,370 

10,520 

0 

297 

7,250 

1924 

Jan. 

8,670 

127,850 

19,030 

8,070 

+   390 

0 

0 

0 

265 

2,300 

Feb. 

15,900 

109,210 

17,800 

15,900 

+   210 

0 

0 

0 

250 

4,250 

Mar. 

11,200 

91,620 

19,030 

11,200 

+   200 

0 

0 

0 

235 

2,620 

April 
May 

53,100 

72,790 

18.410 

30,000 

—    140 

0 

0 

0 

224 

6.940 

60,900 

77,340 

10,030 

31,000 

—   420 

0 

0 

0 

243 

7,530 

June 

4,210 

87,790 

18,410 

4,210 

—   640 

0 

0 

0 

231 

1,000 

July 

1,220 

68,740 

19,030 

1,220 

—   690 

0 

0 

0 

210 

260 

Aug. 

330 

49,020 

19,030 

330 

—   450 

0 

0 

0 

183 

50 

Sept. 

2.980 

29,540 

4,480 

2,980 

-   270 

0 

0 

13.930 

160 

490 

Oct. 

5,340 

24,790 

0 

5,340 

—    110 

0 

0 

19,030 

159 

850 

Nov. 

18,200 

24,680 

0 

18,200 

-+-     40 

0 

0 

18,410 

159 

2,990 

Dec. 
Total  or 
average 

24,600 

24,720 

9,430 

10,950 

+    120 

0 

0 

9,600 

159 

1.750 

206,650 

163,680 

140,000 

-1.760 

0 

0 

60,970 

206 

2,570 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 
RESERVOIR  ON  MOKELUMNE  RIVER. 


321 


FOR  TWO  METHODS  OF  FLOOD  CONTROL. 
tions  Carried  out  on  a  Daily  Basis. 
mary,  see  Table  7,  page  126.) 

Yield  in  municipal  supply  200  million  gallons  daily. 
Installed  capacity  of  power  plant  15,000  k.w. 


Flood  control, 

holding  maximum  reservoir  space  required  (rain-water  floods. 

92,000  ac.-f 

snow-water  floods,  13,000  ac.-ft.)  in  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Clements — rain- 

water  floods. 

5,300  sec.-ft 

;  snow-water  floods,  7,100  sec.-ft. 

Power 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

draft 
through 
turbines 
including 

water 
passed 
for  prior 
rights  in 
acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 
through 

period 

"  of 
operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

Year  and 
month 

1921 

130,000 

19,030 

38.820 

+   530 

21,380 

0 

0 

272 

10,650 

Jan. 

130,000 

17,190 

43,470 

+   420 

860 

0 

0 

272 

13,100 

Feb. 

130,000 

19,030 

54,910 

+    430 

34,490 

0 

0 

273 

15,000 

Mar, 

130,000 

18,410 

43,140 

—   370 

18,340 

0 

0 

277 

12,280 

April 

172,740 

19,030 

41,820 

-1,070 

119,820 

0 

0 

316 

13,270 

May 

209,000 

18,410 

45,460 

—1,460 

112,670 

0 

0 

319 

15,000 

June 

209,000 

19,030 

17.630 

—1,930 

250 

0 

0 

315 

5,560 

July 

190,560 

19,030 

7,750 

—1,550 

0 

0 

0 

304 

2,350 

Aug, 

169,980 

18,410 

5,710 

—   990 

0 

0 

0 

292 

1,720 

Sept. 

150,580 

19,030 

3,000 

—    390 

0 

0 

0 

282 

850 

Oct- 

135,350 

18,410 

0 

+    1.30 

0 

0 

0 

0 

Nov. 

121,600 

19,030 

0 

-f   360 

0 

0 

0 

0 

Dec. 
Total  or 
average 

224,040 

301,710 

—5,890 

307,810 

0 

0 

292 

7,440 

1922 

113,830 

19,030 

1,500 

-f   440 

0 

0 

0 

263 

400 

Jan. 

112,940 

17,190 

15,940 

+   270 

8,980 

0 

0 

268 

4,790 

Feb. 

130,000 

19,030 

46,120 

+   330 

0 

0 

0 

266 

12,230 

Mar. 

121,680 

18,410 

36,930 

—   320 

0 

0 

0 

276 

10,470 

April 

173,020 

19,030 

43,220 

—1,070 

192,240 

25,820 

0 

318 

13,800 

May 

209,640 

18,410 

45,450 

—1,460 

215,320 

0 

0 

319 

15,000 

June 

209,000 

19,030 

25,300 

—1,930 

2,870 

0 

0 

319 

8,080 

July 

199,070 

19,030 

10,100 

—1,630 

0 

0 

0 

308 

3,120 

Aug. 

178.410 

18,410 

7,620 

—1,050 

0 

0 

0 

298 

2,350 

Sept. 

158,950 

19,030 

3,330 

—   400 

0 

0 

0 

286 

950 

Oct. 

144,180 

18,410 

2,210 

+    130 

8,860 

0 

0 

275 

630 

Nov. 

125,530 

19,030 

18,980 

+   390 

16,710 

0 

0 

273 

5,160 

Dec. 

Total  or 
average 

224,040 

256,700 

—6,300 

444,980 

25,820 

0 

291 

6  420 

1923 

130,000 

19,030 

46,120 

+   580 

0 

0 

0 

264 

12,200 

Jan. 

111,630 

17.190 

41,650 

-1-    420 

0 

0 

0 

250 

11,500 

Feb. 

86,510 

19,030 

46,120 

+   430 

0 

0 

0 

228 

10,540 

Mar. 

65,090 

18,410 

34,500 

—   370 

0 

0 

0 

248 

8,610 

April 

138,810 

19,030 

40,790 

—1,070 

93,920 

0 

0 

310 

12,740 

May 

209,000 

18,410 

45,460 

—1,460 

38,670 

0 

0 

319 

15,000 

June 

209,000 

19,030 

22,210 

—1,930 

630 

0 

0 

316 

7.070 

July 

193,700 

19,030 

9,100 

—1,550 

0 

0 

0 

306 

2.780 

Aug. 

173,120 

18,410 

9.040 

—   990 

0 

0 

0 

294 

2,750 

Sept. 

153,720 

19,030 

3,000 

—   390 

0 

0 

0 

284 

850 

Oct. 

140,710 

18,410 

1,760 

-f    120 

2,820 

0 

0 

274 

500 

Nov. 

124,920 

19,030 

0 

-1-   350 

0 

0 

0 

0 

Dec. 
Total  or 

224,040 

299,750 

—5,860 

136,040 

0 

0 

282 

7,010 

average 
1924 

113,190 

19,030 

8,670 

-1-    390 

0 

0 

0 

254 

2,200 

Jan. 

94,550 

17,800 

15,900 

-f    210 

0 

0 

0 

238 

4,050 

Feb. 

76,960 

19,030 

11,200 

+   200 

0 

0 

0 

220 

2,460 

Mar. 

58.130 

18,410 

30,000 

—    140 

0 

0 

0 

207 

6,400 

April 

62,680 

19,030 

31,000 

—   420 

0 

0 

0 

229 

7,030 

May 

73,130 

18,410 

4.210 

—   640 

0 

0 

0 

216 

940 

June 

54,080 

19,030 

1,220 

—   690 

0 

0 

0 

190 

230 

July 

34,360 

9,150 

330 

—   450 

0 

0 

9,880 

1,59 

30 

Aug. 

24,760 

0 

2,980 

—   270 

0 

0 

18,410 

158 

490 

Sept. 

24.490 

0 

5,340 

—    110 

0 

0 

19,030 

158 

850 

Oct. 

24,380 

0 

18,200 

+     40 

0 

0 

18,410 

158 

2,970 

Nov. 

24,420 

9,130 

10,950 

+    120 

0 

0 

9,900 

159 

1,850 

Dec. 
Total  or 

149,020 

140,000 

—1,760 

0 

0 

75,630 

198 

2,450 

average 

322 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  7a  (Concluded).     PARDEE 

COMPARISON  OF  WATER  AND  POWER  YIELD 
Monthly  Summary  of  Computa 


Height  of  dam  345  feet. 

Capacity  of  reservoir  222,000  acre-feet. 


(For  corresponding  yearly  sum 


Run-off 

at 
Clements 

in 
acre-feet 

Flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Clements — rain-water  floods,  5,300  sec.-ft.; 

snow-water  floods,  7,100  sec.-ft. 

Maximum  reservoir  space  required— rain-water  floods  92,000  ac.-ft.; 

snow-water  floods,  13,000  ac.-ft. 

Year  and 
month 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

Power 

draft 

through 

turbines 

including 

water 

passed 

for  prior 

rights  in 

acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets 

in 
acre-feet 

0 

0 

0 

19,410 

108,600 

54,840 

0 

0 

0 

0 

0 

0 

Waste 
over 

spillway 
in 

acre-feet 

Deficiency 

in 

municipal 

supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operat  ion 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor  = 
1.00) 

1925 

Jan. 
Feb. 
Mar. 
April 
May 
June 
July 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
Total  or 

22,500 

107,000 

81,800 

164,000 

237,000 

124,000 

21,000 

10,200 

7,910 

5,560 

7,620 

14,400 

29,060 
31,190 
118,600 
168,130 
222,000 
211,490 
216,910 
200,640 
181,120 
160,720 
143,860 
133,200 

19,030 
17,190 
19,030 
18,410 
19,030 
18,410 
19,030 
19,030 
18,410 
19,030 
18,410 
19,030 

1,500 

2,500 

13,500 

44,680 

46,380 

43,870 

16,310 

10,200 

7.910 

3,000 

0 

0 

+    160 
+    100 
-f   260 

—  290 
—1,070 
—1,460 
—1,930 
—1,490 

—  990 

—  390 
-1-    130 
+   360 

0 
0 
0 
27,340 
72,430 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

172 
231 

280 
315 
323 
321 
320 
310 
298 
288 

260 

640 

3,780 

14,530 

15,000 

14,540 

5,230 

3,160 

2,440 

860 

0 

0 

average 

Total  for 
21 -year 
period, 
1905-1926 

Average 

for 

21-year 

period, 

1905-1928 

802,990 
17,355,000 

828,430 

224,040 
4,646,920 

221,280 

189,850 
5,358,830 

255,170 

—6,610 
122.650 

5,840 

182,850 
5,145,700 

245,030 

99,770 
2,098,030 

99,910 

0 
60,970 

2,900 

286 
292 

5,040 
6,510 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS.  ^  323 

RESERVOIR  ON  MOKELUMNE  RIVER. 

FOR  TWO  METHODS  OF  FLOOD  CONTROL, 
tions  Carried  out  on  a  Daily  Basis. 
mary,  see  Table  7,  page  126.) 

Yield  in  municipal  supply  200  million  gallons  daily. 
Installed  capacity  of  power  plant  15,000  k.w. 


Flood  control,  holding  maximum  reservoir  space  required  (rain-water  floods,  92,000  ac.-ft.: 
snow-water  floods,  13,000  ac.-ft.)  in  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Clements— rain-water  floods,  5,300  sec.-ft. ;  snow-water  floods,  7,100  sec.-ft. 

Stage  of 
reservoir 

at_ 
beginning 

of 
month  in 
acre-feet 

Municipal 

draft 

in 

acre-feet 

Power 

draft 

through 

turbines 

including 

water 

passed 

for  prior 

rights  in 

acre-feet 

Evapora- 
tion in 
acre-feet 

Release 
through 
flood 
control 
outlets 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 
in 

municipal 
supply 

in 
acre-feet 

Average 

power 

head 

through 

period 

of 

operation 

in  feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

Year  and 
month 

29,060 
31,190 
118,600 
130,000 
167,520 
209,000 
209,000 
192,420 
171.900 
152,.500 
135,640 
124,980 

19,030 
17,190 
19,030 
18,410 
19,030 
18,410 
19,030 
19,030 
18,410 
19,030 
18,410 
19,030 

1,500 

2,500 

41,070 

42,570 

43,750 

45,210 

16,620 

10,200 

7,910 

3,000 

0 

0 

+    160 
+    100 
+    260 

—  290 
—1,070 
—1,460 
—1,930 
—1,490 

—  990 

—  390 
+    130 
+    360 

0 

0 

10,560 

65,210 

113,390 

58,920 

0 

0 

0 

0 

0 

0 

0 
0 
0 
0 
18,280 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

172 
231 
272 
278 
318 
319 
316 
306 
294 
282 

260 

640 

11,290 

12,140 

13,970 

14,920 

5,240 

3,120 

2,400 

850 

0 

0 

1925 

Jan. 

Feb. 

Mar. 

April 

May 

June 

July 

Aug. 

Sept. 

Oct. 

Nov. 

Dec. 
Total  or 
average 

Total  for 
21-year 
period, 
1905-1926 

Average 
for 

21 -year 
period, 
1905-1926 

224,040 
4,632,260 

220.580 

214,330 
5,548,880 

264,230 

—6,610 
122,650 

5,840 

248,080 
6,496,310 

309,350 

18,280 
535,750 

25.510 

0 
75,630 

3,600 

279 
283 

5,420 
6,450 

324 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  8a.     PARDEE  RESERVOIR  ON  MOKELUMNE  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  MONTHS 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  6a  and  7a. 

(For  corresponding  yearly  summary,  see  Table  8,  page  128.) 

Height  of  dam  345  feet.  Yield  in  municipal  supply  200  million  gallons  daily. 

Capacity  of  reservoir  222,000  ac.-ft.     Installed  capacity  of  power  plant  15,000  k.w. 


Coordinated  with  flood  control  by 

Flood  control,  holding 

maximum 

reservoir  operating  diagram 

Maximum  controlled  flow  at 
Clements— rain-water  floods. 

reservoir  space  (rain-water  floods, 

92,000  ac.-ft.;  snow-water  floods, 

13,000  ac.-ft.)  in  reserve 

Without  flood  control 

5,300  sec.-ft.;  snow-water 
floods,  7,100  sec.-ft. 

throughout  flood  season 

Maximum  controlled  flow  at 

Year  and 

Maximum  reservoir  space 

required~-rain-water  floods, 

92,000  ac.-ft.;  snow-water 

floods,  13,000  ac.-ft. 

Clements — rain-water  floods, 

5,300  sec.-ft.;  snow-water 

floods,  7,100  sec.-ft. 

month 

Deficiency 

Average 
power 

Deficiency 

Average 
power 

Deficiency 

Average 
power 

Municipal 
draft  in 
acre-feet 

in 

municipal 

supply 

yield  in 

kilowatts 

(Load 

Municipal 
draft  in 
acre-feet 

in 

municipal 

supply 

yield  in 

kilowatts 

(Load 

Municipal 
draft  in 
acre-feet 

municipal 

supply 

in 

yield  in 

kilowatts 

(Load 

in 
acre-feet 

factor= 
1.00) 

in 

acre-feet 

factor= 
1.00) 

acre-feet 

factor= 
1.00) 

1905 

Jan. 

19,030 

0 

2,960 

19,030 

0 

2,960 

19,030 

0 

2,630 

Feb. 

17,190 

0 

7,100 

17,190 

0 

7,100 

17.190 

0 

6.320 

Mar. 

19,030 

0 

13,370 

19,030 

0 

13,370 

19,030 

0 

12,020 

April 

18,410 

0 

14.380 

18,410 

0 

14,380 

18,410 

0 

12,810 

May 

19,030 

0 

15,000 

19,030 

0 

15,000 

19,030 

0 

11,870 

June 

18,410 

0 

13,700 

18,410 

0 

13,540 

18,410 

0 

13,720 

July 

19,030 

0 

3,680 

19,030 

0 

3,680 

19.030 

0 

3,620 

Aug. 

19,030 

0 

2,430 

19,030 

0 

2,420 

19.030 

0 

2,370 

Sept. 

18,410 

0 

2,540 

18,410 

0 

2,530 

18,410 

0 

2,470 

Oct. 

19,030 

0 

860 

19,030 

0 

860 

19,030 

0 

830 

Nov. 

18,410 

0 

0 

18,410 

0 

0 

18,410 

0 

0 

Dec. 
Total  or 
average 

19,030 

0 

0 

19,030 

0 

0 

19,030 

0 

0 

224,040 

0 

6,320 

224,040 

0 

6,300 

224,040 

0 

5,700 

1906 

Jan. 

19.030 

0 

0 

19.030 

0 

0 

19,030 

0 

2,770 

Feb. 

17,190 

0 

13,050 

17,190 

0 

13,020 

17,190 

0 

12,160 

Mar. 

19,030 

0 

13,680 

19,030 

0 

12,880 

19,030 

0 

13,700 

April 

18,410 

0 

15,000 

18,410 

0 

14,220 

18,410 

0 

11,720 

May 

19,030 

0 

15,000 

19.030 

0 

15.000 

19,030 

0 

13.370 

Juno 

18,410 

0 

15,000 

18,410 

0 

15,000 

18,410 

0 

15,000 

July 

19,030 

0 

14,500 

19,030 

0 

14,,500 

19,030 

0 

14,310 

Aug. 

19,030 

0 

10,130 

19,030 

0 

10,130 

19,030 

0 

10,130 

Sept. 

18,410 

0 

3,650 

18,410 

0 

3,650 

18,410 

0 

3,650 

Oct. 

19,030 

0 

1,920 

19,030 

0 

1,920 

19,030 

0 

1,920 

Nov. 

18,410 

0 

900 

18,410 

0 

900 

18,410 

0 

2,250 

Dec. 
Total  or 
average 

19,030 

0 

1,470 

19,030 

0 

3,370 

19,030 

0 

5,390 

224,040 

0 

8,650 

224,040 

0 

8.680 

224,040 

0 

8,850 

1907 

Jan. 

19,030 

0 

14,010 

19,030 

0 

14,050 

19.030 

0 

12,820 

Feb. 

17,190 

0 

14,930 

17,190 

0 

15,000 

17,190 

0 

15,000 

Mar. 

19,030 

0 

15,000 

19,030 

0 

14,950 

19,030 

0 

15,000 

April 
May 

18,410 

0 

15,000 

18,410 

0 

15,000 

18,410 

0 

11.780 

19,030 

0 

15,000 

19,030 

0 

15,000 

19,030 

0 

15.000 

June 

18,410 

0 

15,000 

18,410 

0 

15.000 

18,410 

0 

15,000 

July 

19,030 

0 

15,000 

19,030 

0 

15,000 

19,030 

0 

14.810 

Aug. 

19,030 

0 

10,130 

19,030 

0 

10,130 

19,030 

0 

10,130 

Sept. 

18.410 

0 

9.810 

18,410 

0 

9.810 

18,410 

0 

9,810 

Oct. 

19,030 

0 

2,840 

19,030 

0 

2,840 

19,030 

0 

2,840 

Nov. 

18.410 

0 

2,710 

18,410 

0 

2,710 

18,410 

0 

3,900 

Deo. 
Total  or 
average 

19,030 

0 

860 

19,030 

0 

860 

19,030 

0 

810 

224,040 

0 

10,820 

224,040 

0 

10,820 

224,040 

0 

10,560 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


325 


TABLE  8a    (Continued).     PARDEE  RESERVOIR  ON  MOKELUMNE  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  MONTHS 

BOTH 
WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  6a  and  7a. 

(For  corresponding  yearly  summary,  see  Table  8,  page  128.) 

Height  of  dam  345  feet.  Yield  in  municipal  supply  200  million  gallons  daily. 

Capacity  of  reservoir  222,000  ac.-ft.     Installed  capacity  of  power  plant  15,000  k.w 


326 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  8a    (Continued).     PARDEE  RESERVOIR  ON  MOKELUMNE  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  MONTHS 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  6a  and  7a. 

(For  corresponding  yearly  summary,  see  Table  8,  page  128.) 

Height  of  dam  345  feet.  Yield  in  municipal  supply  200  million  gallons  daily. 

Capacity  of  reservoir  222,000  ac.-ft.     Installed  capacity  of  power  plant  15,000  k.w. 


Without  flood  control 

Coordinated  with  flood  control  by 
reservoir  operating  diagram 

Maximum  controlled  flow  at 

Clements — rain-water  floods , 

5,300  sec.-ft.;  snow-water 

floods,  7,100  sec.-ft. 

Maximum  reservoir  space 

required — rain-water  floods, 

92,000  ac.-ft.:  snow-water 

floods,  13,000  ac.-ft. 

Flood  control,  holding  maximum 
reservoir  space  (rain-water  Roods, 

92,000  ac.-ft.;  snow-water  floods, 
13,000  ac.-ft.)  in  reserve 
throughout  flood  season 

Maximum  controlled  flow  at 

Year  and 

Clements-  -rain-water  floods, 

5,300  sec.-ft.;  snow-water 

floods,  7,100  sec.-ft. 

month 

Deficiency 

Average 
power 

Deficiency 

Average 
power 

Deficiency 

Average 
power 

Municipal 
draft  in 

in 

municipal 

supply 

jield  in 
kilowatts 

Municipal 
draft  in 

in 

mimicipal 

supply 

yield  in 
lalowatts 

Mimicipal 
draft  in 

in 

municipal 

supply 

>neld  in 
kilowatts 

acre-feet 

(Load 

acre-feet 

(Load 

acre-feet 

(Load 

in 
acre-feet 

factor= 
1.00) 

in 
acre-feet 

factor= 
1.00) 

in 
acre-feet 

factor= 
1.00) 

1911 

Jan. 

19,030 

0 

2,430 

19,030 

0 

5,090 

19,030 

0 

7,470 

Feb. 

17,190 

0 

15.000 

17.190 

0 

14,910 

17,190 

0 

14,960 

Mar. 

19,030 

0 

15,000 

19,030 

0 

15,000 

19,030 

0 

15,000 

April 

18,410 

0 

15,000 

18,410 

0 

15,000 

18,410 

0 

11,740 

May 

19,030 

0 

15,000 

19,030 

0 

15,000 

19,030 

0 

14,090 

June 

18,410 

0 

15,000 

18,410 

0 

15.000 

18,410 

0 

15,000 

July 

19.030 

0 

13,130 

19,030 

0 

13,130 

19.030 

0 

12.620 

Aug. 

19,030 

0 

8.360 

19,030 

0 

8,360 

19,030 

0 

8.360 

Sept. 

18,410 

0 

3,580 

18,410 

0 

3,580 

18,410 

0 

3,580 

Oct. 

19,030 

0 

1,170 

19,030 

0 

1,170 

19,030 

0 

1,170 

Nov. 

18,410 

0 

0 

18,410 

0 

0 

18,410 

0 

1,000 

Dec. 
Total  or 
average 

19,030 

0 

550 

19,030 

0 

550 

19,030 

0 

540 

224,040 

0 

8,630 

224,040 

0 

8,850 

224,040 

0 

8,750 

1912 

Jan. 

19,030 

0 

790 

19,030 

0 

790 

19,030 

0 

750 

Feb. 

17,800 

0 

2,260 

17,800 

0 

2,260 

17,800 

0 

2,140 

Mar. 

19,030 

0 

5,980 

19.030 

0 

5.980 

19,030 

0 

5,630 

April 

18.410 

0 

8,040 

18,410 

0 

8,040 

18,410 

0 

7,170 

May 

19,030 

0 

7,650 

19,030 

0 

7,650 

19,030 

0 

7,190 

June 

18,410 

0 

10,920 

18.410 

0 

10,920 

18.410 

0 

10.600 

July 

19,030 

0 

3,150 

19,030 

0 

3,150 

19,030 

0 

3,080 

Aug. 

19,030 

0 

1,720 

19,030 

0 

1,720 

19.030 

0 

1.680 

Sept. 

18,410 

0 

2,010 

18,410 

0 

2,010 

18,410 

0 

1,960 

Oct. 

19,030 

0 

860 

19,030 

0 

860 

19,030 

0 

830 

Nov. 

18,410 

0 

0 

18.410 

0 

0 

18,410 

0 

510 

Dec. 
Total  or 
average 

19,030 

0 

3,090 

19,030 

0 

3,090 

19,030 

0 

2,920 

224,650 

0 

3,870 

224,650 

0 

3.870 

224,650 

0 

3,700 

1913 

Jan. 

19,030 

0 

690 

19,030 

0 

690 

19,030 

0 

650 

Feb. 

17.190 

0 

5,540 

17.190 

0 

6,540 

17,190 

0 

5,180 

Mar. 

19,030 

0 

8,760 

19.030 

0 

8,760 

19.030 

0 

8,010 

April 
May 

18,410 

0 

8,930 

18.410 

0 

8,930 

18,410 

0 

7,750 

19,030 

0 

9,370 

19,030 

0 

9.370 

19,030 

0 

8,600 

June 

18,410 

0 

10,790 

18,410 

0 

10,790 

18,410 

0 

9,040 

July 

19.030 

0 

3,320 

19,030 

0 

3,320 

19,030 

0 

3,250 

Aug. 

19,030 

0 

2,550 

19,030 

0 

2,550 

19,030 

0 

2,490 

Sept. 

18.410 

0 

1,930 

18.410 

0 

1,930 

18,410 

0 

1,880 

Oct. 

19,030 

0 

850 

19,030 

0 

850 

19.030 

0 

820 

Nov. 

18,410 

0 

0 

18,410 

0 

0 

18,410 

0 

0 

Deo. 
Total  or 
average 

19,030 

0 

0 

19,030 

0 

0 

19,030 

0 

0 

224,040 

0 

4,370 

224,040 

0 

4,370 

224,040 

0 

3,950 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS, 


327 


TABLE  8a    (Continued).     PARDEE  RESERVOIR  ON  MOKELUMNE  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  MONTHS 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  6a  and  7a. 

(For  corresponding  yearly  summary,  see  Table  8,  page  128.) 

Height  of  dam  345  feet.  Yield  in  municipal  supply  200  million  gallons  daily. 

Capacity  of  reservoir  222,000  ac.-ft.     Installed  capacity  of  power  plant  15,000  k.w. 


Without  flood  control 

Coordinated  with  flood  control  by 
reservoir  operating  diagram 

Maximum  controlled  flow  at 

Clements— rain-water  floods, 

5,300  sec.-ft.;  snow-water 

floods, 7,100  sec.-ft. 

Maximum  reservoir  space 

required— rain-water  floods, 

92,000  ac.-ft.;  snow-water 

floods,  13,000  ac.-ft. 

Flood  control,  holding  maximum 

reservoir  space  (rain-water  floods, 

92,000  ac.-ft.;  snow-water  floods, 

13,000  ac.-ft.)  in  reserve 

throughout  flood  season 

Maximum  controlled  flow  at 

Year  and 

Clements — rain-water  floods, 

5,300  sec.-ft.;  snow-water 

floods,  7,100  sec.-ft. 

month 

Deficiency 

Average 
power 

Deficiency 

Average 
power 

Deficiency 

Average 
power 

Municipal 
draft  in 

in 

municipal 

supply 

yield  in 
kilowatts 

Municipal 
draft  in 

in 

municipal 

supply 

yield  in 
kilowatts 

Municipal 
draft  in 

m 

municipal 

supply 

yiold  in 
kilowatts 

acre-feet 

(Load 

acre-feet 

(Load 

acre-feet 

(Load 

in 
acre-feet 

factor= 
1.00) 

in 
acre-feet 

factor= 
1.00) 

in 
acre-feet 

factor= 
1.00) 

1914 

Jan. 

19,030 

0 

3,270 

19,030 

0 

11,160 

19,030 

0 

12,030 

Feb. 

17,190 

0 

15,000 

17,190 

0 

12,920 

17,190 

0 

13,660 

Mar. 

19,030 

0 

15,000 

19,030 

0 

12,840 

19,030 

0 

15,000 

April 

18,410 

0 

15,000 

18,410 

0 

13,060 

18,410 

0 

11,440 

May 

19,030 

0 

15,000 

19,030 

0 

15,000 

19,030 

0 

12,930 

June 

18,410 

0 

15,000 

18,410 

0 

15,000 

18,410 

0 

15,000 

July 

19,030 

0 

10,160 

19,030 

0 

10,130 

19,030 

0 

9,150 

Aug. 

19,030 

0 

6.330 

19,030 

0 

6,330 

19,030 

0 

3,760 

Sept. 

18,410 

0 

3,330 

18,410 

0 

3,330 

18,410 

0 

3,330 

Oct. 

19,030 

0 

2,000 

19,030 

0 

2,000 

19,030 

0 

2,000 

Nov. 

18,410 

0 

0 

18,410 

0 

0 

18,410 

0 

500 

Dec. 

19,030 

0 

0 

19,030 

0 

0 

19,030 

0 

0 

Total  or 
average 

224,040 

0 

8,280 

224,040 

0 

8,4.50 

224,040 

0 

8,200 

1915 

Jan. 

19,030 

0 

400 

19,030 

0 

400 

19,030 

0 

400 

Feb. 

17,190 

0 

4,270 

17,190 

0 

6,860 

17,190 

0 

10,890 

Mar. 

19,030 

0 

13,490 

19,030 

0 

5,480 

19,030 

0 

12,370 

April 

18,410 

0 

14,310 

18,410 

0 

14,310 

18,410 

0 

11,780 

May 

19,030 

0 

15,000 

19,030 

0 

15,000 

19,030 

0 

12.810 

June 

18,410 

0 

15,000 

18,410 

0 

15,000 

18,410 

0 

15,000 

July 

19,030 

0 

9,300 

19,030 

0 

9,130 

19,030 

0 

8,280 

Aug. 

19,030 

0 

3,050 

19.030 

0 

3,050 

19,030 

0 

1,770 

Sept. 

18,410 

0 

2,920 

18,410 

0 

2,920 

18,410 

0 

1,970 

Oct. 

19,030 

0 

1,160 

19,030 

0 

1,160 

19,030 

0 

860 

Nov. 

18,410 

0 

0 

18,410 

0 

0 

18,410 

0 

500 

Dec. 

19,030 

0 

0 

19,030 

0 

0 

19,030 

0 

0 

Total  or 
average 

224,040 

0 

6,580 

224,040 

0 

6,080 

224,040 

0 

6,340 

1916 

Jan. 

19,030 

0 

1,900 

19,030 

0 

8,510 

19,030 

0 

9,890 

Feb. 

17,800 

0 

14,740 

17,800 

0 

14,470 

17,800 

0 

14,740 

Mar. 

19,030 

0 

15,000 

19,030 

0 

14,990 

19,030 

0 

15,000 

April 

18,410 

0 

15,000 

18,410 

0 

14,510 

18,410 

0 

11,720 

May 

19,030 

0 

15.000 

19,030 

0 

15,000 

19,030 

0 

14,330 

June 

18,410 

0 

15,000 

18,410 

0 

14,970 

18,410 

0 

15,000 

July 

19,030 

0 

10,500 

19,030 

0 

9,850 

19,030 

0 

9,090 

Aug. 

19,030 

0 

6,100 

19,030 

0 

6,100 

19,030 

0 

3,980 

Sept. 

18,410 

0 

3,000 

18,410 

0 

3,000 

18,410 

0 

3,000 

Oct. 

19,030 

0 

1,730 

19,030 

0 

1,730 

19,030 

0 

1,730 

Nov. 

18,410 

0 

1,170 

18,410 

0 

1,170 

18,410 

0 

1,710 

Dec. 

19,030 

0 

280 

19,030 

0 

280 

19,030 

0 

1,510 

Total  or 
average 

224,650 

0 

8,240 

224,650 

0 

8.690 

224,650 

0 

8,450 

328 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  8a    (Continued).     PARDEE  RESERVOIR  ON  MOKELUMNE  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  MONTHS 

BOTH 
WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  6a  and  7a. 
(For  corresponding  yearly  summary,  see  Table  8,  page  128.) 

Height  of  dam  345  feet.  Yield  in  municipal  supply  200  million  gallons  daily. 

Capacity  of  reservoir  222,000  ac.-ft.     Installed  capacity  of  power  plant  15,000  k.w, 


Year  and 

Without  flood  control 

Coordinated  with  flood  control  by 
reservoir  operating  diagram 

Maximum  controlled  flow  at 

Clements— rain-water  floods, 

5,300  sec.-ft.;  snow-water 

floods,  7,100  sec.-ft. 

Maximum  reservoir  space 

required — rain-water  floods, 

92,000  ac.-ft.;  snow-water 

floods,  13,000  ac.-ft. 

Flood  control,  holding  maximum 

reservoir  space  (rain-water  floods, 

92,000  ac.-ft.:  snow-water  floods, 

13,000  ac.-ft.)  in  reserve 

throughout  flood  season 

Maximum  controlled  flow  at 

Clements — rain-water  floods. 

5,300  sec.-ft.;  snow-water 

floods,  7,100  sec.-ft. 

month 

Deficiency 

Average 
power 

Deficiency 

Average 
power 

Deficiency 

Average 
power 

Municipal 
Jraf t  in 

in 

municipal 

supply 

yield  in 
kilowatts 

Municipal 
draft  in 

in 

municipal 

supply 

yield  in 
kilowatts 

Municipal 
draft  in 

in 

municipal 

supply 

yield  in 
kilowatts 

acre-feet 

(Load 

acre-feet 

(Load 

acre-feet 

(Load 

in 
acre-feet 

factor= 
1.00) 

in 

acre-feet 

faotor= 
1.00) 

in 
acre-feet 

factor= 
1.00) 

1917 

Jan. 

19,030 

0 

5,390 

19,030 

0 

5,390 

19,030 

0 

5.200 

Feb. 

17,190 

0 

4,640 

17,190 

0 

5,360 

17,190 

0 

5,890 

Mar. 

19,030 

0 

13,430 

19,030 

0 

8,150 

19,030 

0 

12,580 

April 

18,410 

0 

14,100 

18,410 

0 

14,100 

18,410 

0 

10,880 

May 

19,030 

0 

15,000 

19,030 

0 

15,000 

19,030 

0 

13,640 

June 

18,410 

0 

15,000 

18,410 

0 

15,000 

18,410 

0 

15,000 

July 

19,030 

0 

9,580 

19,030 

0 

9,580 

19,030 

0 

8,440 

Aug. 

19,030 

0 

5,130 

19.030 

0 

5,130 

19,030 

0 

2.960 

Sept. 

18,410 

0 

2,690 

18.410 

0 

2,690 

18.410 

0 

2,690 

Oct. 

19,030 

0 

1,160 

19,030 

0 

1,160 

19,030 

0 

1,160 

Nov. 

18,410 

0 

0 

18,410 

0 

0 

18,410 

0 

500 

Dec. 

19,030 

0 

0 

19,030 

0 

0 

19,030 

0 

0 

Total  or 
average 

224,040 

0 

7,190 

224,040 

0 

6,790 

224,040 

0 

6,580 

1918 

Jan. 

19,030 

0 

380 

19,030 

0 

380 

19,030 

0 

380 

Feb. 

17,190 

0 

2,620 

17,190 

0 

2.620 

17,190 

0 

2,080 

Mar. 

19,030 

0 

3,990 

19,030 

0 

3,990 

19,030 

0 

8,240 

April 

18,410 

0 

14,100 

18,410 

0 

14,100 

18,410 

0 

12,750 

May 

19,030 

0 

15,000 

19,030 

0 

15,000 

19,030 

0 

13,290 

June 

18,410 

0 

12,640 

18,410 

0 

12,640 

18,410 

0 

12,580 

July 

19,030 

II 

2,510 

19,030 

0 

2,510 

19,030 

0 

2,460 

Aug. 

19,030 

(1 

1,490 

19,030 

0 

1,490 

19,030 

0 

1,450 

Sept. 

18,410 

0 

2,690 

18,410 

0 

2,690 

18.410 

0 

2,610 

Oct. 

19,030 

0 

860 

19,030 

0 

800 

19,030 

0 

830 

Nov. 

18,410 

0 

0 

18,410 

0 

0 

18,410 

0 

70 

Dec. 
Total  or 
average 

19,030 

0 

0 

19,030 

0 

0 

19,030 

0 

U 

224,040 

0 

4,680 

224.040 

0 

4.680 

224,040 

0 

4,730 

1919 

Jnn. 

19,030 

0 

1,630 

19,030 

0 

1,630 

19,030 

0 

1,570 

Feb. 

17,190 

0 

3,150 

17,190 

0 

3,150 

17.190 

0 

3,050 

Mar. 

19,030 

0 

12,590 

19,0.30 

0 

12,590 

19,030 

0 

12,180 

April 

18,410 

0 

13,400 

18.410 

0 

13,400 

18,410 

0 

12,250 

May 

19,030 

0 

15,000 

19,030 

0 

15,000 

19,030 

0 

14,490 

Juno 

18,410 

0 

8.130 

18,410 

0 

8,130 

18,410 

0 

8,080 

July 

19.030 

0 

1.7.50 

19,030 

0 

1,750 

19,030 

0 

1,710 

Aug. 

19.030 

0 

1,490 

19,030 

0             1,490 

19,030 

0 

1.450 

Sept. 

18.410 

0 

1.560 

18,410 

0            1,560 

18,410 

0              1.510 

Oct. 

19.0.30 

0 

830 

19,030 

0               830 

19,030 

0                 810 

Nov. 

18,410 

0 

0 

18,410 

0 

0 

18.410 

0 

0 

Dec. 
Total  or 
average 

19,030 

0 

0 

19.030 

0 

0 

19.030 

0 

0 

224,040 

0 

4.970 

224.040 

0 

4,970 

224.040 

0 

4.760 

THE   CONTROL   OP   FLOODS   BY   RESERVOIRS. 


321) 


TABLE  8a    (Continued).     PARDEE  RESERVOIR  ON  MOKELUMNE  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  MONTHS 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  6a  and  7a. 

(For  corresponding  yearly  summary,  see  Table  8,  page  128.) 

Height  of  dam  345  feet.  Yield  in  municipal  supply  200  million  gallons  daily. 

Capacity  of  reservoir  222,000  ac.-ft.     Installed  capacity  of  power  plant  15,000  k.w. 


Without  flood  control 

Coordinated  with  flood  control  by 
reservoir  operating  diagram 

Maximum  controlled  flow  at 

Clements — rain-water  floods, 

5,300  sec.-ft.;  snow- water 

floods,  7,100  sec.-ft. 

Flood  control,  holding  maximum 

reservoir  space  (rain-water  floods, 

92,000  ac.-ft.;  snow-water  floods, 

13,000  ac.-ft.)  in  reserve 

throughout  flood  season 

Maximum  controlled  flow  at 

Year  and 

Maximum  reservoir  space 

required — rain-water  floods, 

92,000  ac.-ft.;  snow-water 

floods,  13,000  ac.-ft. 

Clements — rain-water  floods, 

5,300  sec.-ft.:  snow-water 

floods,  7,100  sec.-ft. 

month 

Deficiency 

Average 
power 

Deficiency 

Average 
power 

Deficiency 

Average 
power 

1 

Municipal 
draft  in 

municipal 
supply 

yield  in 
kilowatts 

Municipal 
draft  in 

municipal 
supply 

yield  in 
kilowatts 

acre-feet        ^^PP'^ 

yield  in 
kilowatts 

1 

acre-feet 

(Load 

acre-feet 

(Load 

(Load 

1 

in 
acre-feet 

factor= 
1.00) 

in 
acre-feet 

factor= 
1.00) 

acre-feet 

factor^ 
1.00) 

1920 

Jan. 

19,030 

0 

380 

19,030  1                0 

380 

19,030 

0 

360 

Feb. 

17,800 

0 

650 

17,800 

0 

650 

17,800 

0 

620 

Mar. 

19,03» 

0 

4,680 

19,030 

0 

4,680 

19,030 

0 

4,440 

.\pril 

18,410 

0 

9,110 

18,410 

0 

9,110 

18,410 

0 

8,250 

May 

19,030 

0 

10.990 

19,030 

0 

10.990 

19,030 

0 

10,980 

June 

18,410 

0 

12,830 

18,410 

0 

12,830 

18,410 

0 

12,760 

July 

19,030 

0 

4,400 

19,030 

0 

4,400 

19,030 

0 

4,300 

.\ug. 

19,030 

0 

1,800 

19,030 

0 

1,800 

19,030 

0 

1,760 

Sept. 

18,410 

0 

1,490 

18,410 

0 

1,490 

18,410 

0 

1,440 

Oct. 

19,030 

0 

860 

19,030 

0 

860 

19,030 

0 

830 

Nov. 

18,410 

0 

0 

18,410 

0 

0 

18,410 

0 

920 

Dec. 
Total  or 
average 

19,030 

0 

0 

19,030 

0 

0 

19,030 

0 

4,090 

224,650 

0 

3,930 

224,650 

0 

3,930 

224,650 

0 

4,230 

1921 

Jan. 

19.030 

0 

7,630 

19,030 

0 

13,200 

19,030 

0 

10,650 

Feb. 

17,190 

0 

14,420 

17,190 

0 

11,620 

17,190 

0 

13,100 

Mar. 

19,030 

0 

14,910 

19,030 

0 

10,970 

19,030 

0 

15,000 

April 

18.410 

0 

15,000 

18,410 

0 

10,400 

18,410 

0 

12,280 

May 

19,030 

0 

15,000 

19.030 

0 

15,000 

19,030 

0 

13,270 

June 

18,410 

0 

15,000 

18,410 

0 

14,850 

18,410 

0 

15,000 

July 

19,030 

0 

5,690 

19,030 

0 

5,420 

19,030 

0 

5,560 

.^ug. 

19,030 

0 

2,410 

19,030 

0 

2,410 

19,030 

0 

2,350 

Sept. 

18,410 

0 

1,780 

18.410 

0 

1,760 

18,410 

0 

1,720 

Oct. 

19,030 

0 

870 

19.030 

0 

860 

19,030 

0 

850 

Nov. 

18,410 

0 

0 

18,410 

0 

0 

18,410 

0 

0 

Dec. 

19.030 

0 

0 

19,030 

0 

0 

19,030 

0 

0 

Total  or 
average 

224.040 

0 

7,660 

224,040 

0 

7,170 

224,040 

0 

7,440 

1922 

Jan. 

19,030 

0 

400 

19,030 

0 

400 

19,030 

0 

400 

Feb. 

17,190 

0 

940 

17.190 

0 

2,650 

17,190 

0 

4,790 

Mar. 

19,030 

0 

13,310 

19,030 

0 

9.790 

19,030 

0 

12.230 

April 

18,410 

0 

13,690 

18,410 

0 

13,690 

18,410 

0 

10.470 

May 

19,030 

0 

14,970 

19,030 

0 

14,970 

19,030 

0 

13.800 

June 

18,410 

0 

15,000 

18,410 

0 

15,000 

18,410 

0 

15,000 

July 

19,030 

0 

8,900 

19,030 

0 

8,900 

19.030 

0 

8,080 

Aug. 

19,030 

0 

4,720 

19,030 

0 

4,720 

19,030 

0 

3,120 

Sept. 

18,410 

0 

3,280 

18.410 

0 

3,280 

18,410 

0 

2,350 

Oct. 

19,030 

0 

1,140 

19,030 

0 

1,140 

19,030 

0 

950 

Nov. 

18.410 

0 

0 

18.410 

0 

0 

18,410 

0 

630 

Dec. 
Total  or 
average 

19,030 

0 

0 

19,030 

0 

0 

19,030 

0 

5.160 

224,040 

0 

6.390 

224,040 

0  [         6,220 

224,040 

0 

6,420 

21—52 

ni 

330 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  8a    (Concluded).     PARDEE  RESERVOIR  ON  MOKELUMNE  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  MONTHS 

BOTH 
WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  6a  and  7a. 
(For  corresponding  yearly  summary,  see  Table  8,  page  128.) 

Height  of  dam  345  feet.  Yield  in  municipal  supply  200  million  gallons  daily. 

Capacity  of  reservoir  222,000  ac.-ft.     Installed  capacity  of  power  plant  15,000  k.w. 


Without  flood  control 

Coordinated  with  flood  control  by 
reservoir  operating  diagram 

Maximum  controlled  flow  at 

Clements — rain-water  floods, 

5,300  sec.-ft.;  snow-water 

floods,  7,100  sec.-ft. 

Flood  control,  holding  maximum 

reservoir  space  (rain-water  floods, 

92,000  ac.-ft.:  snow-water  floods, 

13,000  ac.-ft.)  in  reserve 

throughout  flood  season 

Maximum  controlled  flow  at 

Year  and 

Maximum  reservoir  space 

required — rain-water  floods, 

92,000  ac.-ft.;  snow-water 

floods,  13,000  ac.-ft. 

Clements — rain-water  flood.s, 

5,300  sec.-ft.;  snow-water 

floods,  7,100  sec.-ft. 

month 

Deficiency 

Average 
power 

Deficiency 

Average 
power 

Deficiency 

Average 
power 

Municipal 
draft  in 

in 

municipal 

supply 

yield  in 
kilowatts 

Mimicipal 
draft  in 

in 

municipal 

supply 

yield  in 
kilowatts 

Municipal 
draft  in 

in 

municipal 

supply 

yield  in 
kilowatts 

acre-feet 

(Load 

acre-feet 

(Load 

acre-feet 

(Load 

in 
acre-feet 

factor= 
1.00) 

in 
acre-feet 

factor= 
1.00) 

in 
acre-feet 

factor= 
1.00) 

1923 

Jan. 

19,030 

0 

13,560 

19,030 

0 

12,770 

19.030 

0 

12,200 

Feb. 

17,190 

0 

13,050 

17,190 

0 

5,980 

17,190 

0 

11,500 

Mar. 

19,030 

0 

12.340 

19,030 

0 

12,340 

19,030 

0 

10,540 

April 

18,410 

0 

13,010 

18,410 

0 

13,010 

18,410 

0 

8.610 

May- 

19.030 

0 

14,790 

19,030 

0 

14,790 

19,030 

0 

12,740 

June 

18,410 

0 

15,000 

18,410 

0 

14,830 

18,410 

0 

15,CM)0 

July 

19,030 

0 

7.330 

19.030 

0 

6.670 

19.030 

0 

7.070 

Aug. 

19,030 

0 

2,850 

19,030 

0 

2.840 

19,030 

0 

2.780 

Sept. 

18,410 

0 

2.820 

18,410 

0 

2,810 

18,410 

0 

2,750 

Oct. 

19.030 

0 

870 

19,030 

0 

870 

19,030 

0 

850 

Nov. 

18,410 

0 

0 

18,410 

0 

0 

18,410 

0 

500 

Dec. 
Total  or 
average 

19,030 

0 

0 

19,030 

0 

0 

19,030 

0 

0 

224,040 

0 

7,930 

224,040 

0 

7.250 

224,040 

0 

7,010 

1924 

Jan. 

19,030 

0 

2,310 

19,030 

0 

2,300 

19,030 

0 

2,200 

Feb. 

17,800 

0 

4,300 

17,800 

0 

4,250 

17.800 

0 

4.050 

Mar. 

19,030 

0 

2.650 

19,030 

0 

2.620 

19,030 

0 

2.460 

.\pril 

18.410 

0 

6,970 

18,410 

0 

6.940 

18,410 

0 

6.400 

May 

19,030 

0 

7,580 

19,030 

0 

7,530 

19.030 

0 

7,030 

June 

18,410 

0 

1,010 

18,410 

0 

1,000 

18.410 

0 

940 

July 

19.030 

0 

260 

19.030 

0 

260 

19,030 

0 

230 

Aug. 

19,030 

0 

70 

19,030 

0 

50 

9,150 

9.880 

30 

Sept. 

6,770 

11,640 

500 

4.480 

13,930 

•490 

0 

18,410 

490 

Oct. 

0 

19,030 

850 

0 

19,030 

850 

0 

19,030 

850 

Nov. 

0 

18,410 

2,990 

0 

18,410 

2,990 

0 

18,410 

2,970 

Dec. 
Total  or 
average 

9.470 

9.560 

1,750 

9,430 

9,600 

1,750 

9,130 

9,900 

1,850 

166.010 

58,640 

2.590 

163,680 

60,970 

2,570 

149,020 

75,630 

2.450 

1925 

Jan. 

19.030 

0 

260 

19.030 

0 

260 

19,030 

0 

•260 

Feb. 

17,190 

0 

640 

17.190 

0 

640 

17,190 

0 

640 

Mar. 

19,030 

0 

3,780 

19.030 

0 

3,780 

19.030 

0 

11,2'.)0 

April 

18,410 

0 

14,530 

18,410 

0 

14,530 

18,410 

0 

12  141) 

May 

19,030 

0 

15,000 

19,030 

0 

15.000 

19.030 

0 

13,970 

June 

18,410 

0 

15,000 

18,410 

0 

14,540 

18,410 

0 

14,920 

July 

19.030 

0 

5,390 

19,030 

0 

5,230 

19.030 

0 

5.240 

Aug. 

19,030 

0 

3.190 

19,030 

0 

3,160 

19,030 

0 

3.120 

Sept. 

18.410 

0 

2,470 

18,410 

0 

2,440 

18,410 

0 

2.400 

Oct. 

19,030 

0 

870 

19,030 

0 

860 

19,030 

0 

850 

Nov. 

18.410 

0 

0 

18.410 

0 

0 

18,410 

0 

0 

Dec. 
Totel  or 
average 

19,030 

0 

0 

19,030 

0 

0 

19.030 

0 

0 

224.040 

0 

5.100 

224.040 

0 

5.040 

224,040 

0 

5,420 

Total  for 

21-year 

period. 

-     -    — 

- — 

— 

1905-1926 

4.649,250 

58,640 

4,646,920 

60,970 

4,632,260 

75.630 

Average 
for 

21-year 

period, 

1905-1926 

221,390 

2,790 

6,640 

221,280 

2,900 

6,510 

220,580 

3,600 

6,450 

THE    CONTROL   OF    FLOODS   BY    RESERVOIRS.  331 

ASSUMPTIONS  EMPLOYED  IN  COMPUTING  WATER  AND  POWER  YIELD 
OF  TEMPERANCE  FLAT  RESERVOIR  ON  SAN  JOAQUIN  RIVER  ON 
A  DAILY  BASIS. 

1.  The  water  siip])ly  at  the  dam  site  is  the  same  as  that  measured  at 
the  Friant  araofinp^  station  of  the  TTnited  States  Geological  Survey  and 
published  or  in  preparation  for  publication,  as  mean  dail.y  discharges 
in  the  Water  Supply  Papers.  No  deductions  were  made  for  down- 
stream prior  rights. 

2.  The  reservoir  is  full  on  June  1,  1907,  the  opening  date  of  the 
estimates.  The  run-off  index  for  the  season  1906-1907  is  156.  The 
reservoir  fills  in  1917  with  a  run-off  index  of  94. 

3.  The  net  evaporation  from  the  reservoir  surface  equals  4.0  feet 
depth  per  annum,  divided  among  the  months  as  follows : 

Per  cent 
Depth  in  of  seasonal 

Month  feet  total 

April    0.37  9.2 

May   0.;50  12.6 

.Tune 0.60  15.0 

July   0.71  17.8 

August 0.66  16.6 

September 0.51  12.7 

October    0.39  9.6 

Xovember 0.26  6.5 

Totals 4.00  100.0 

4.  The  total  .seasonal  draft  from  the  reservoir  for  irrigation  is 
divided  among  the  months  as  f o11o"\\t^  :  (The  summer  peak  of  the  irri- 
gation demand  is  carried  by  pumping  from  wells.) 

Demand  in  per 
cent  of  total 
Month  seasonal  use 

.January — 0.0 

February    2.6 

March 6.6 

April 14.5 

May 14.5 

.Tune    14.5 

July 14.5 

August    14.5 

September    13.1 

October 5.2 

November 0.0 

December 0.0 

Total 100.0 

5.  The  seasonal  irrigation  yield  is  that  which  can  be  obtained  from  the 
reservoir  during  the  period  1872-1925  with  a  deticiency,  when  supple- 
mented by  pumping  from  ground  water,  not  oftener  on  the  average 
than  one  year  in  18. 

6.  Power  is  generated  in  a  plant  at  the  ba-se  of  the  dam  with  water 
drawn  from  the  reservoir  for  irrigation  and  with  reservoir  spill.  The 
load  factor  is  1.00  and  the  power  factor  0.80. 

7.  Secondary  power  is  intermittent  power. 

IB  8.  The  overall  plant  efficiency  increa.se.s  from  75.0  per  cent  at  full 
reservoir  to  78.7  per  cent  at  0.8  depth  and  then  decreases  to  73.5  per 
cent  at  0.5  depth. 

9.  The  elevation  of  the  tail  race  rises  18  feet  when  20,000  second- 
feet  are  passing  the  dam,  13  feet  when  30,000  second-feet  are  passing, 
8  feet  when  5000  second-feet  are  passing,  and  corresponding  amounts 

i    for  other  flows. 


-.V.i'l 


WATER  RESOURCES  OF    CALIFORNIA. 

TABLE  9a      TEMPERANCE  FLAT  RESER 


WATER  AND  POWER  YIELD  BOTH  WITH  AND  WITHOUT 
Monthly  Summary  of  Computations 

(For  corresponding  yearly  sum 
Seasonal  irrigation  yield,  1,800,000  acre-feet.   (Supplemented  by  ground  water 
Height  of  dam  595  feet.     Capacity  of  reservoir  1,071,000  acre-feet. 


Run-off 

at 
Friant 

Without  flood  control 

Irrigation 

Average 

Year  and 
month 

Stage  of 
reservoir 

draft  in 
acre-feet 

Power 

Waste 

Deficiency 

power 
head 

.Average 
power 

in 
acre-feet 

at 

(no 

Evapora- 

draft 

over 

in 

irrigation 

supply 

through 

yield  in 

beginning 

deduction 

tion  in 

through 

spillway 

period 

lulowatts 

of 

for  down- 

acre-feet 

turbines 

in 

of 

(Load 

month  in 
acre-feet 

stream 
prior 
rights) 

in  acre-feet 

acre-feet 

in 
acre-feet 

operation 
in 
feet 

factor= 
1.00) 

1908 

Jan. 

53,100 

797,100 

0 

0 

0 

0 

0 

0 

Feb. 

.18.100 

850,200 

47,000 

0 

47.000 

0 

0 

548 

29  200 

Mar. 

120,000 

861,300 

119,000 

0 

119.000 

0 

0 

543 

68,400 

.\pril 

199,000 

862,300 

261.000 

1,700 

261.000 

0 

0 

530 

152,400 1 

May 

219,000 

798,600 

261,000 

2,200 

261,000 

0 

0 

522 

145,800 

June 

176,000 

754,400 

261.000 

2,600 

261,000 

0 

0 

507 

146,900 

July 

119,000 

666,800 

261,000 

2.800 

261.000 

0 

0 

478 

135,100 

Aug. 

"3,200 

522,000 

261.000 

2,300 

261,000 

0 

0 

429 

121,100 

Sept. 

39.000 

331,900 

236,000 

1,300 

228,100 

0 

0 

347 

86,800 

Oct. 

23,900 

133,600 

93,000 

000 

0 

0 

0 

0 

Nov. 

16,200 

63,900 

0 

200 

0 

0 

0 

0 

Dec. 
Total  or 
average 

18,500 

79,900 

0 

0 

0 

0 

0 

0 

1,11.5,000 

1,800,000 

13,700 

1.699,100 

0 

0 

488 

73,800 

1909 

Jan. 

277,000 

98,400 

0 

0 

0 

0 

0 

0 

Feb. 

183,000 

375,400 

47,000 

0 

47.000 

0 

0 

4.38 

24,700 

Mar. 

133,000 

511,400 

119,000 

0 

119,000 

0 

0 

460 

59.300 

.\pril 

3.52,000 

525,400 

261.000 

1,300 

261,000 

0 

0 

459 

1.34,200 

May 

646,000 

615,100 

261,000 

1,900 

261,000 

0 

0 

531 

147.700 

June 

827,000 

998,200 

261,000 

3,100 

265,400 

485,700 

0 

574 

164.200 

July 

309,000 

1,071,000 

261.000 

3,800 

268,000 

82,900 

0 

578 

161,000 

Aug. 

78,100 

1,025,300 

261,000 

3,500 

261,000 

0 

0 

554 

152,400 

Sept. 

37,000 

838,900 

236,000 

2,400 

236,000 

0 

0 

512 

134.200 

Oct 

25.000 

637,500 

93,000 

1,500 

93,000 

0 

0 

482 

48,500 

Nov. 

49,600 

568.000 

0 

900 

0 

0 

0 

0 

Dec. 
Total  or 
average 

220,000 

616.700 

0 

0 

0 

0 

0 

0 

3,136.700 

1.800,000 

18.400 

1,811.400 

568,600 

0 

510 

85.800 

1910 

.)uii. 

188,000 

836,700 

0 

0 

0 

0 

0 

0 

Feb. 

86,600 

1,024,700 

47,000 

0 

47.000 

0 

0 

586 

31. .500 

Mar. 

188,000 

1,064,300 

119,000 

0 

181,300 

0 

& 

584 

10!>.7O0 

April 

375,000 

1.071.000 

261,000 

2,000 

262,400 

110,600 

0 

580 

I6:i,.i00 

May 

475,000 

1,071,000 

261,000 

2,700 

273,300 

199.000 

0 

579 

164,400 

June 

237.000 

1,071,000 

261,000 

3,200 

261,600 

37,700 

0 

578 

162,600 

July 

99,600 

1,005,500 

261,000 

3,700 

261.000 

0 

0 

554 

152,300 

Aug. 

39,600 

840,400 

261,000 

3.100 

261,000 

0 

0 

509 

142,900 

Sept. 

51,700 

615,900 

2.36,000 

1.900 

236.000 

0 

0 

456 

120,400 

Oct. 

29,600 

429,700 

93,000 

1,200 

93.000 

0 

0 

419 

42,200 

Nov. 

24,000 

365,100 

0 

700 

0 

0 

0 

0 

Dec. 

31.400 

388.400 

0 

0 

0 

0 

0 

0 

Total  or 
avor;iKe 

1,825.500 

1,800,000 

18,500 

1.876,600 

347,300 

0 

538 

91.100 

1911 

Jan. 

239,000 

419.800 

0 

0 

0 

0 

0 

0 

Feb. 

207,000 

658,800 

47,000 

0 

47,000 

0 

0 

526 

29,200 

Mur 

336,000 

818,800 

119,000 

0 

119,000 

0 

0 

558 

69,900 

April 

425,000 

1,035.800 

261,000 

1,900 

264,000 

123,900 

0 

578 

164.300 

May 

571,000 

1.071,000 

261,000 

2,700 

273,400 

294,900 

0 

578 

164.400 

Juiii- 

940,000 

1.071,000 

201.000 

3,200 

265,600 

677,200 

0 

575 

164.400 

July 

593,000 

1.071,000 

261.000 

3,800 

272,700 

320,500 

0 

576 

163.400 

Aug. 

116.000 

1.067,000 

261.000 

3,500 

261,000 

0 

0 

569 

155.200 

Sept. 

45.500 

918,500 

236.000 

2.400 

236,000 

0 

0 

532 

138,200 

Oct. 

32,300 

725,600 

93,000 

1.600 

93,000 

0 

0 

507 

50,700 

Nov. 

28.000 

663,.30O 

0 

1,000 

0 

0 

0 

0 

Dec. 
Total  or 
average 

23.400 

690.300 

0 

0 

0 

0 

0 

0 

3,.S62.200 

1,800,000 

20,100 

1,831,700 

1,416,500 

0 

556 

91,900 

THE    CONTROL   OF    I-^LOODS   BY    RESERVOIRS. 


333 


VOIR  ON  SAN  JOAQUIN  RIVER. 

FLOOD  CONTROL  BY  RESERVOIR  OPERATING  DIAGRAM. 
Carried  out  on  a  Daily  Basis. 

mary,  see  Table  9,  page  134.) 

supply  in  years  of  deficiency.     No  deduction  for  downstream  prior  rights.) 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.P.  =0.80. 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Friant — rain-water  floods,  IC 

,700  sec.-ft 

snow-water 

floods,  14,200  sec.-ft. 

Maximum  reservoir 

space  reauired— rain-water  floods,  133,000  ac.-ft.; 

snow-water  floods.  177,000  ac.-ft. 

Irrigation 

Average 

Stage  of 
reservoir 

draft  in 
acre-feet 

Power 

Release 
through 
flood 
control 
oatlets  in 
iicre-feet 

Waste 

Deficiency 

power 
head 

Average 
power 

Year  and 
month 

at 

(no 

Evapor?- 

draft 

over 

in 

irrigation 

supply 

through 

yield  in 

beginning 

dedaction 

tion  in 

through 

spillway 

period 

kilowatts 

of 

for  down- 

acre-feet 

turbines 

in 

of 

(Load 

month  in 
acre-feet 

stream 
prior 

in  acre-feet 

acre-feet 

in 
acre-feet 

operation 
in 

factor= 
1.00) 

rights) 

feet 

1908 

797,100 

0 

0 

0 

0 

0 

0 

0 

Jan. 

850,200 

47,000 

0 

47,000 

0 

0 

0 

548 

29,200 

Feb. 

861.300 

119,000 

0 

119,000 

0 

0 

0 

543 

68,400 

Mar. 

862,300 

261,000 

1,700 

261,000 

0 

0 

0 

530 

152,400 

April 

798,600 

261,000 

2.200 

261,000 

0 

0 

0 

522 

145,800 

Mav 

75-1.400 

261.000 

2.600 

261,000 

0 

0 

0 

507 

146,900 

.June 

666.800 

261.000 

2,800 

261,000 

0 

0 

0 

478 

135,100 

July 

522,000 

261.000 

2.300 

261,000 

0 

0 

0 

429 

121,100 

.^ug. 

331,900 

236.000 

1.300 

228,100 

0 

0 

0 

347 

86,800 

Sept. 

133,600 

93.000 

600 

0 

0 

0 

0 

0 

Oct. 

63,900 

0 

200 

0 

0 

0 

0 

0 

Nov. 

79,900 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,800,000 

13,700 

1,699,100 

0 

0 

0 

488 

73,800 

1903 

98.400 

0 

0 

0 

0 

0 

0 

0 

Jan. 

375,400 

47,000 

0 

47,000 

0 

0 

0 

438 

24,700 

Feb. 

511,400 

119,000 

0 

119,000 

0 

0 

0 

460 

59,300 

Mar. 

525,400 

261.000 

1.300 

261,000 

0 

0 

0 

459 

134,200 

April 

61.S,100 

261.000 

1.900 

266,400 

86,700 

0 

0 

529 

150,300 

May 

906,100 

261.000 

2.900 

273,000 

484,800 

0 

0 

553 

164,400 

June 

972,400 

261,000 

3.600 

263,900 

34,400 

0 

0 

568 

156.000 

July 

979..500 

261,000 

3,400 

261,000 

0 

0 

0 

543 

1.50.300 

Aug. 

793,200 

236,000 

2,300 

236.000 

0 

0 

0 

500 

131,400 

Sept. 

591,900 

93,000 

1,500 

93,000 

0 

0 

0 

468 

47,200 

Oct. 

522,400 

0 

900 

0 

0 

0 

0 

0 

Nov. 

571,100 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Tntal  or 
average 

1,800,000 

17,800 

1,820,300 

605,900 

0 

0 

503 

85,100 

1910 

791,100 

0 

0 

0 

0 

0 

0 

0 

Jan. 

979,100 

47,000 

0 

87,600 

900 

0 

0 

567 

57,600 

Feb. 

977,200 

119.000 

0 

123,200 

0 

0 

0 

574 

73,800 

Mar. 

1,042,000 

261.000 

1.900 

262,200 

33,800 

66,.500 

0 

576 

162,600 

.\pril 

1,052,600 

261,000 

2.700 

280,900 

328,800 

0 

0 

556 

164,400 

May 

91.5,200 

261.000 

2.900 

263,300          37,800 

0 

0 

547 

157,400 

June 

848,200 

261.000 

3.300 

261,000 

0 

0 

0 

520 

145,200 

July 

683,500 

261.000 

2,700 

261.000 

0 

0 

0 

469 

132,700 

Aug. 

4.59.400 

236.000 

1.600 

236,000 

0 

0 

0 

398 

104,900 

S;pt. 

273.500 

93,000 

900 

93,000 

0 

0 

0 

357 

35,500 

Oct. 

209,200 

0 

500 

0 

0 

0 

0 

0 

Nov. 

232.700 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  Df 
average 

1,800,000 

16,500 

1,868,200 

401,300 

66,500 

0 

506 

86,200 

1911 

264.100 

0 

0 

0                   0 

0 

0 

0 

Jan. 

.503.100 

47,000 

0 

47,000                   0 

0 

0 

489 

27,500 

Feb. 

663,100 

119,000 

0 

119,000  1                0 

0 

0 

525 

66,700 

Mar. 

880,100 

261,000 

1,800 

261,000  1                0 

0 

0 

561 

158,900 

Anril 

1,042.300 

261.000 

2,600 

280,000         430,500 

0 

0 

557 

164,000 

May 

900,200 

261,000 

2,900 

272,300         541,900 

0 

0 

555 

164,400 

Ju"e 

1,029,100 

261,000 

3,700 

273,100         203,700 

74,600 

0 

574 

163,300 

July 

1,067,000 

261,000 

3,.500 

261,000                   0 

0 

0 

569 

155.200 

Aug. 

918,500 

236.000 

2.400  :      236,000  ;                0  1 

0 

0 

532 

138,200 

S-pt. 

725,600 

93,000 

1.600 

93,000                   0 

0 

0 

507 

50,700    1 

Oct. 

663,300 

0 

1,000 

0                   0 

0 

0 

0 

Nov. 

690,300 

0 

0 

0                   0 

0 

0 

0 

Dec. 
To  h1  or 
aver  ige 

1,800,000 

19,500 

1,842,400 

1,176,100 

74,600 

0 

542 

91,000 

334 


WATER  RESOURCES   OF    CALIFORNIA. 


TABLE  9a  (Continued).     TEMPERANCE  FLAT 

WATER  AND  POWER  YIELD  BOTH  WITH  AND  WITHOUT 

Monthly  Summary  of  Computations 

(For  correspx)nding  yearly  sum 
Seasonal  irrigation  yield,  1,800,000  acre-feet.   (Supplemented  by  ground  water 
Height  of  dam  595  feet.     Capacity  of  reservoir  1,071,000  acre-feet. 


Run-off 

at 
Friant 

in 
acre-feet 

Without  flood  cofilrol 

Year  and 
month 

SUgeof 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Irrigation 
draft  in 
acre-feet 

(no 
deduction 
for  down- 
stream 
prior 
rights) 

Evapora- 
tion in 
acre-feet 

Power 

draft 

through 

tiirbines 

in  acre-feet 

Waste 

over 
spillway 

in 
acre-feet 

Deficiency 

in 

irrigation 

supply 

in 
acre-feet 

•Average 

power 

head 

through 

period 

of 

operation 

in 

feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor=: 
1.00) 

1912 

Jan. 
Feb. 
Mar. 
April 
May 
June 
July 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
Total  or 

30,100 
26,600 
55,200 
75,000 
255,000 
368,000 
95,300 
38,000 
22,400 
17,800 
20,300 
20,000 

713,700 

743,800 

723,400 

659,600 

472,100 

464,500 

569,600 

401,300 

176,400 

0 

0 

20,300 

0 

47,000 
119,000 
261,000 
261,000 
261,000 
261,000 
261,000 
198,100 

17,800 
0 
0 

0 

0 

0 

1,500 

1,600 

1,900 

2,600 

1,900 

700 

0 

0 

0 

0 

47,000 

119,000 

261,000 

261,000 

261,000 

261.000 

261,000 

39.300 

0 

0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
37,900 
75,200 
0 
0 

52i 
505 

468 
431 
472 
445 
367 
305 

0 

28.000 
64,700 
136,700 
121,8001 
137,900» 
125,800^ 
102,70W 
12,80O«, 

1 

avpragp 

1913 

Jan. 
Feb. 
Mar. 
April 
May 
June 
July 
Aug. 
Sppt. 
Oct. 
Nov. 
Dec. 
Total  or 

1,023,700 

22,100 
25,700 
38,200 
95,800 
247,000 
170,000 
102,000 
68,900 
40,600 
12,800 
22.300 
28,700 

40,300 

62,400 

41,100 

0 

0 

27.800 

0 

0 

0 

0 

0 

22,300 

1,686,900 

0 

47,000 

79,300 

95,800 

219,200 

197.700 

102,000 

68,900 

40,600 

12,800 

0 

0 

10,200 

0 
0 
0 
0 
0 
100 
0 
0 
0 
0 
0 
0 

1,510,300 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

113,100 

0 

0 

39,700 

165,200 

41,800 

63,300 

159,000 

192,100 

195,400 

80.200 

0 

0 

454 

60,900 

0 
0 
0 
0 
0 

average 

1914 
Jan. 
Feb. 
Mar. 
April 
May 
June 
July 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
Total  or 

874,100 

259,000 

145,000 

234,000 

395.000 

577,000 

607,000 

392,000 

142,000 

53,900 

40,300 

30,.5O0 

29,600 

51,000 
310,000 
408.000 
523.000 
655,700 
969,700 
1,071,000 
1,007,200 
944,700 
760.100 
705.700 
735.100 

863.300 

0 

47,000 

119,000 

261,000 

261,000 

261,000 

261,000 

261,000 

236,000 

93.000 

0 

0 

100 

0 

0 

0 

1,300 

2,000 

3,000 

3,800 

3,500 

2,500 

1,700 

1,100 

0 

0 

0 

47,000 

119,000 

261,000 

261,000 

263,700 

269,900 

261,000 

236,000 

93,000 

0 

0 

0 

0 
0 
0 
0 
0 
239.000 
122,100 
0 
0 
0 
0 
0 

936,700 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 

404 
439 
475 
520 
578 
579 
573 
537 
514 

0 

0 

22,800 
56,60Ot 

Hsison 

163,80i 
162,508 
156.1001 
139.30g 

avpragp 

1915 

.Ian. 
FpI.. 
Mar. 
April 
May 
June 
July 
Aug. 
Sept. 
Oct. 
Nov. 
Dee. 
Total  or 

2,905.300 

38,200 

90,000 

124,000 

246.000 

381.000 

686.000 

287.000 

70.100 

44,300 

26.700 

23.400 

37,900 

764.700 
802.900 
845,900 
850,900 
834,200 
951,900 
1.071.000 
1,037,400 
813,000 
648.900 
581,100 
603,500 

1.800,000 

0 

47,000 

119,000 

261,000 

261,000 

261,009 

261,000 

261.000 

236,000 

93.000 

0 

0 

18,900 

0 

0 

0 

1,700 

2,300 

3.000 

3.800 

3,500 

2,400 

1.500 

1,000 

0 

1,811,600 

0 

47,000 

119,000 

261,000 

261,000 

263,400 

266.900 

261.000 

236.000 

93.000 

0 

0 

361,100 

0 
0 
0 
0 
0 
200,500 
49,900 
0 
0 
U 
0 
0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

514 

5.38 
539 
533 
541 
577 
579 
557 
514 
485 

esiiol 

153,10^ 
149,90*. 
163.300' 
160,800' 
ISS.OML 
134.60y 
48,800^ 
0 
0 

average 

1.954.600 

1,800,000 

19.200 

1.808.300 

250,400 

0 

540 

88.70«t 

■  ^ 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


335 


RESERVOIR  ON  SAN  JOAQUIN  RIVER. 

FLOOD  CONTROL  BY  RESERVOIR  OPERATING  DIAGRAM. 
Carried  out  on  a  Daily  Basis. 

mary,  see  Table  9,  page  134.) 

supply  in  years  of  deficiency.     No  deduction  for  downstream  prior  rights, ) 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.P.  =  0.80. 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Frbnt — rain-water  floods,  10,700  sec.-ft.; 

snow-water  floods,  14,200  sec.-ft 

Maximum  reservoir 

space  required — rain-water  floods,  133,000  ac.-ft.; 

snow-water  floods,  177,000  ac.  ft. 

Irrigation 

Average 

Stage  of 

draft  in 

Relepse 

through 

flood 

cojitrol 
outlets  in 
acre-feet 

Deficiency 

pOWrt 

Average 

Year  and 

reservoir 

acre-feet 

Power 

Waste 

head 

power 

month 

at 

(no 

Evapora- 

draft 

over 

in 

irrigation 

supply 

through 

yield  in 

lieginnmg 

deduction 

tion  in 

through 

spillway 

period 

kilowatts 

of 

for  down- 

acre-feet 

tiirbines 

in 

of 

(Load 

month  in 
acre-feet 

stream 
prior 

in  acre-feet 

acre-feet 

in 
acre-feet 

operation 
in 

factor= 
1.00) 

rights) 

feet 

1912 

713,700 

0 

0 

0 

0 

0 

0 

0 

.Jan. 

743,800 

47,000 

0 

47,000 

0 

0 

0 

52  i 

28,000 

Feb. 

723,400 

119,000 

0 

119,000 

0 

0 

0 

505 

64.700 

Mar. 

653,600 

261,000 

1,500 

261,000 

0 

0 

0 

468 

136,700 

April 

472,100 

261,000 

1,600 

261,000 

0 

0 

0 

431 

121,800 

May 

461,500 

261,000 

1,900 

261,000 

0 

0 

0 

472 

137,900 

.Tunc 

569,600 

261,000 

2,600 

261,000 

0 

0 

0 

445 

125.800 

July 

401.300 

261,000 

1,900 

261,000 

0 

0 

0 

367 

102.700 

Aug. 

176,400 

198,100 

700 

39,300 

0 

0 

37,900 

305 

12,800 

Sept. 

0 

17,800 

0 

0 

0 

0 

75,200 

0 

Oct. 

0 

0 

0 

0 

0 

0 

0 

0 

Nov. 

20,300 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,686,900 

10,200 

1,510,300 

0 

0 

113,100 

454 

60,900 

1913 

40,300 

0 

0 

0 

0 

0 

0 

0 

Jan. 

62,400 

47,000 

0 

0 

0 

0 

0 

0 

Feb. 

41,100 

79,300 

0 

0 

0 

0 

39,700 

0 

Mar. 

0 

95,800 

0 

0 

0 

0 

165,200 

■  •  1 

0 

April 

0 

219,200 

0 

0 

0 

0 

41,800 

0 

May 

27,800 

197,700 

100 

0 

0 

0 

63,300 

- 

0 

June 

0 

102,000 

0 

0 

0 

0 

159,000 

0 

July 

0 

68,900 

0 

0 

0 

0 

192,100 

0 

Aug. 

0 

40,600 

0 

0 

0 

0 

195,400 

0 

Sept. 

0 

12,800 

0 

0 

0 

0 

80,200 

0 

Oct. 

0 

0 

0 

0 

0 

0 

0 

0 

Nov. 

22,300 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

863,300 

100 

0 

0 

0 

936,700 

0 

0 

1914 

51,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

310,000 

47,000 

0 

47,000 

0 

0 

0 

404 

22,800 

Feb. 

408,000 

119,000 

0 

119,000 

0 

0 

0 

439 

56,600 

Mar. 

523,000 

261,000 

1,300 

261,000 

0 

0 

0 

475 

138,800 

April 

655,700 

261,000 

2,000 

264,300 

66,800 

0 

0 

519 

146,800 

May 

899,600 

261,000 

2,900 

275,100 

264,900 

0 

0 

547 

164,400 

June 

963,700 

261,000 

3,600 

265,000 

26,200 

0 

0 

574 

158,600 

July 

1,000,900 

261.000 

3.500 

261,000 

0 

0 

0 

573 

156,100 

Aug. 

938,400 

236,000 

2,500 

236,000 

0 

0 

0 

537 

139,000 

Sept. 

753,800 

93,000 

1,700 

93,000 

0 

0 

0 

513 

51,200 

Oct. 

699,400 

0 

1,100 

0 

0 

0 

0 

0 

Nov. 

728.800 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

1,800,000 

18,600 

1,821,400 

357,900 

0 

0 

510 

86,400 

1915 

758,400 

0 

0 

0 

0 

0 

0 

0 

Juii. 

7%,600 

47,000 

0 

47,000 

0 

0 

0 

537 

29,600 

Feb. 

839,600 

119,000 

0 

119,000 

0 

0 

0 

537 

67,900 

Mar. 

844,600 

261,000 

1,700 

261,000 

0 

0 

0 

532 

152,800 

Anril 

827,900 

261,000 

2,300 

264,100 

44,300 

0 

0 

538 

151,100 

May 

898,200 

261,000 

2,900 

275,200 

241,300 

0 

0 

547 

164,400 

June 

964,800 

261,000 

3,600 

263,300 

2,}00 

0 

0 

508 

156,500 

Jdy 

982,800 

261,000 

3,400 

261,000 

0 

0 

0 

.545 

150,700 

Aug. 

788,500 

236,000 

2,300 

236,000 

0 

0 

1) 

500 

131,400 

Sept. 

594,500 

93,000 

1,500 

93,000 

0 

0 

0 

466 

47,000 

Oct. 

523,700 

0 

900 

0 

0 

0 

0 

0 

Nov. 

549,200 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Total  >:t 
average 

1,800,000 

18,600 

1,819,600 

287.700 

0 

0 

530 

87,800 

336 


WATER  RESOURCES  OP   CALIFORNIA. 


TABLE  9a  (Continued).     TEMPERANCE  FLAT 

WATER  AND   POWER  YIELD  BOTH  WITH  AND  WITHOUT 
Monthly  Summary  of  Computations 

(For  corresponding  yearly  sum 
Seasonal  irrigation  yield,  1,800,000  acre-feet.  'Supplemented  by  ground  water 
Height  of  dam  595  feet.     Capacity  of  reservoir  1,071,000  acre-feet. 


Run-off 

Without  flood  control 

Irrigation 

Average 

Year  and 

at 

Stage  of 

draft  in 

Deficiency 

power 

-Average 

month 

Friant 

reservoir 

acre-feet 

Power 

Waste 

in 

head 

power 

in 

at 

fno 

Evapora- 

draft 

o\er 

irrigation 

through 

yield  in 

acre-feet 

beginning 

deduction 

tion  in 

through 

spillway 

supply 

period 

kilowatts 

of 

for  down- 

acrc-fect 

turbines 

in 

in 

of 

(I-oad 

month  in 

stream 

in  acre-feet 

arre-feet 

acre-feet 

operation 

factor= 

acre-feet 

prior 

in 

1.00) 

rights) 

feet 

1916 

Jan. 

173,000 

641,400 

0 

0 

0 

0 

0 

0 

Feb. 

142,000 

814,400 

47,000 

0 

47,000 

0 

0 

545 

29.000 

Mar. 

338,000 

909,400 

119,000 

0 

162,100 

14,300 

0 

.571 

97,000 

.\pril 

477,000 

1,071.000 

261,000 

2,000 

264,000 

211.000 

0 

580 

164,400 

.May 

5-52,000 

1.071,000 

261,000 

2,700 

273.300 

276,000 

0 

578 

164,400 

.June 

572,000 

1,071,000 

201,000 

3.200 

264,800 

304,000 

0 

578 

164.400 

.luly 

289,000 

1.071,000 

261.000 

3,800 

267,600 

44,300 

0 

580 

161,300 

.\ug. 

91,000 

1,044,300 

261,000 

3,.500 

261,000 

0 

0 

561 

153,800 

Sept. 

44,900 

870,800 

236,000 

2,400 

236,000 

0 

0 

520 

135,800 

Oct. 

63,900 

677,300 

93.000 

1,600 

93,000 

0 

0 

499 

50,100 

Nov. 

38,900 

646,600 

0 

1,000 

0 

0 

0 

0 

Dec. 

45,300 

684,500 

0 

0 

0 

0 

0 

0 

Total  or 
average 

2.827,000 

1,800,000 

20,200 

1,868,800 

840,600 

0 

557 

93,500 

1917 

Jan. 

47,500 

729,800 

0 

0 

0 

0 

0 

0 

Feb. 

129.000 

777,300 

47,000 

0 

47,000 

0 

0 

53i 

29.500 

Mar. 

108,000 

859.300 

119,000 

0 

119,000 

0 

0 

542 

68,400 

.April 

226,000 

848.300 

261,000 

1,700 

261,000 

0 

0 

530 

152,500 

May 

373,000 

811. 6C0 

261,000 

2.,300 

261.000 

0 

0 

.540 

149,600 

June 

579,000 

921,.300 

261.000 

3.000 

262.500 

163.800 

0 

575 

162,600 

July 

222,000 

1,071,000 

261.000 

3.800 

264,200 

13,100 

0 

579 

159,100 

Aug. 

72,600 

1,011,900 

261,000 

3.400 

261.000 

0 

0 

5.53 

152,200 

Sept. 

36,100 

820,100 

236,000 

2,300 

236.000 

0 

0 

507 

133,200 

Oct. 

25,400 

617,900 

93,000 

1,500 

93,000 

0 

0 

477 

48,000 

Nov. 

21,900 

548,800 

0 

900 

0 

0 

0 

0 

Dec. 

19,600 

569,800 

0 

0 

0 

0 

0 

0 

Total  or 
average 

1.860,100 

1,800,000 

18,900 

1,804,700 

176,900 

0 

537 

88.100 

1918 

Jan. 

20,500 

.589,400 

0 

0 

0 

0 

0 

0 

Feb. 

36,800 

609,900 

47,000 

0 

47.000 

0 

0 

484 

27,200 

Mar. 

149,000 

599,700 

119,000 

0 

119,000 

0 

0 

483 

62,200 

.\pril 

179,000 

629,700 

261,000 

1,400 

261,000 

0 

0 

477 

139,300 

May 

307.000 

646,300 

261,000 

1,800 

261,000 

0 

0 

470 

132,900 

June 

494.000 

590.500 

261,000 

2.200 

261,000 

0 

0 

510 

147,800 

July 

121,000 

821,300 

261,000 

3,400 

261,000 

0 

0 

517 

144,600 

•Aug. 

42,800 

677.900 

261,000 

2,700 

261,000 

0 

0 

467 

132,100 

Sept. 

48,700 

457,000 

236,000 

1,600 

236,000 

0 

0 

403 

106.100 

Oct. 

103,000 

268,100 

93,000 

900 

93,000 

0 

0 

382 

38,,300 

Nov. 

44.000 

277,200 

0 

600 

0 

0 

0 

0 

Dec. 

Total  or 
.Tvoriigo 

50,700 

320,600 

0 

0 

0 

0 

0 

0 

1.596,500 

1,800,000 

14,600 

1,800,000 

0 

0 

466 

77,700 

1919 

Jan. 

38,400 

371,300 

0 

0 

0 

0 

0 

0 

Feb. 

68.900 

409.700 

47,000 

0 

47,000 

0 

0 

4.30 

24..300 

Mar. 

94.100 

431,600 

119,000 

0 

119,000 

0 

0 

427 

.55,000 

.\pril 

209,000 

406,700 

261.000 

1,100 

261,000 

0 

0 

407 

118,600 

May 

441,000 

353,600 

261,000 

1,300 

261,000 

0 

0 

430 

121,500 

June 

l.'>4,000 

532,300 

261,000 

2.100 

261,000 

0 

0 

447 

130,600 

July 

61,500 

423,200 

261,000 

2,100 

261.000 

0 

0 

389 

109,500 

Aug. 

30,400 

221,600 

250,300 

1,700 

92,600 

0 

10,700 

320 

30,800 

Sept. 

23,000 

0 

23,000 

0 

0 

0 

213,000 

0 

Oct. 

22,400 

0 

22,400 

0 

0 

0 

70,600 

0 

Nov. 

18,600 

0 

0 

0 

0 

0 

0 

(1 

Dec. 
Total  or 
average 

30.100 

18,600 

0 

0 

0 

0 

0 

0 

1,191.400 

1,505.700 

8,300 

1,302.600 

0 

294,300 

416 

49,200 

THE    CONTROL    OF    FLOODS   BY    RESERVOIRS.  'S'M 

RESERVOIR  ON  SAN  JOAQUIN  RIVER. 

FLOOD  CONTROL  BY  RESERVOIR  OPERATING  DIAGRAM. 
Carried  out  on  a  Daily  Basis. 

mary,  see  Table  9,  page  134.) 

supply  in  years  of  deficiency.     No  deduction  for  downstream  prior  rights.) 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.P.  =  0.80. 


Coordinated  with  flood  control  by  reservoir  ooeratlnq  diaaram 

Maximum  controlled  flow  at  Friant— rain-water  floods,  10 

,700nec.-ft.; 

snow-water  floods,  14,200  sec.-ft. 

Maximum  reserv:,ir 

space  required— rain-wat 

er  floods,  133,000  ac.-ft.: 

mow-water  flood.s,  177,000  ac.-ft. 

Stage  of 

Irrigation 

Average 

reservoir 

at 
beginning 

of 
month  in 
acre-feet 

draft  in 
acre-feet 

(no 
deduction 
for  down- 
stream 
prior 
rights) 

Eyapora- 
tion  in 
acre-feet 

Power 

draft 

through 

turbines 

in  acre-feet 

Release 

through 

flood 

control 
outlets  in 
acre-feet 

Waste 
over 

spillway 
in 

acre-feet 

Deficiency 
in 

irrigation 
supply 

in 
acre- feet 

power 

head 

through 

period 

of 

operation 

in 

feet 

Average 
power 

yield  in 

kilowatts 
(Load 

factor = 
1.00) 

Year  and 
month 

1916 

587.100 

0 

0 

0 

0 

0 

0 

0 

.Ian. 

760,100 

47,000 

0 

47.000 

0 

0 

0 

532 

28,400 

Feb. 

855,100 

119,000 

0 

122,100 

0 

0 

0 

562 

72,000 

Mar. 

1.071,000 

261,000 

2,000 

264.300 

0 

210,700 

0 

579 

164,400 

A  Til 

1,071,000 

261.000 

2,700 

280.100 

417,600 

21,.500 

0 

558 

161,400 

May 

901,100 

261,000 

2,900 

274.000 

226,000 

0 

0 

549 

104,300 

.lunp 

909,600 

201,000 

3,600 

261.000 

0 

0 

0 

569 

155,400 

Julv 

994,000 

261,000 

3.400 

261,000 

0 

0 

0 

551 

151,700 

Aug. 

820,600 

2.36,000 

2,300 

236,000 

0 

0 

0 

509 

133,300 

Sept. 

627,200 

93,000 

1,.500 

93,000 

0 

0 

0 

486 

48,900 

Oct. 

596,600 

0 

1,000 

0 

0 

0 

0 

0 

Nov. 

634,500 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,800,000 

19,400 

1,838,500 

644,200 

232,200 

0 

544 

90,300 

1917 

679,800 

0 

0 

0 

0 

0 

0 

0 

Jan. 

727,300 

47,000 

0 

47,000 

0 

0 

0 

519 

28,900 

Feb. 

809,300 

119,000 

0 

119,000 

0 

0 

0 

531 

07,300 

Mar. 

798,300 

261,000 

1,700 

261,000 

0 

0 

0 

518 

149,700 

April 

761,600 

261,000 

2.200 

261,000 

0 

0 

0 

530 

147,400 

May 

871,400 

261,000 

2,800 

262,900 

57,600 

56,100 

0 

569 

161,400 

June 

1,071,000 

261,000 

3.800 

264,200 

0 

13,100 

0 

579 

159,100 

July 

1,011,900 

261,000 

3.400 

261,000 

0 

0 

0 

553 

152,200 

Aug. 

820,100 

236,000 

2,300 

230,000 

0 

0 

0 

507 

133,200 

Sept. 

617,900 

93,000 

1,500 

93,000 

0 

0 

0 

477 

48,000 

Oct. 

548,800 

0 

900 

0 

0 

0 

0 

0 

Nov. 

569,800 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,800,000 

18,600 

1,805,100 

57,600 

69,200 

0 

532 

87,500 

1918 

589,400 

0 

0 

0 

0 

0 

0 

0 

Jan. 

609,900 

47,000 

0 

47,000 

0 

0 

0 

484 

27,200 

Feb. 

599,700 

119,000 

0 

119,000 

0 

0 

0 

483 

62,200 

Mar. 

629,700 

261,000 

1,400 

261,000 

0 

0 

0 

477 

139,300 

.\pril 

546.300 

261,000 

1,800 

261,000 

0 

0 

0 

470 

132,900 

Mav 

590,500 

261,000 

2,200 

261,000 

0 

0 

0 

510 

147,800 

June 

821,300 

261,000 

3,400 

261,000 

0 

0 

0 

517 

144,600 

Julv 

677,900 

261,000 

2,700 

261,000 

0 

0 

0 

467 

132.100 

A  UK. 

457,000 

235,000 

1,000 

236,000 

0 

0 

0 

403 

106.100 

S"p(. 

268,100 

93,000 

900 

93,000 

0 

0 

0 

382 

38.300 

Oct. 

277,200 

0 

600 

0 

0 

0 

0 

0 

Nov. 

320.600 

0 

0 

0 

0 

0 

0 

0 

Dec. 

1,800,000 

14,600 

1,800,000 

0 

0 

0 

466 

77,700 

Total  or 

avonigr 

1919 

371,.300 

0 

0 

0 

0 

0 

0 

0 

Jan. 

409,700 

47,000 

0 

47,000 

0 

0 

0 

430 

24,300 

Feb. 

431,600 

119,000 

0 

119,000 

0 

0 

0 

427 

55,000 

Mar. 

406,700 

261,000 

1,100 

261,000 

0 

0 

0 

407 

118,600 

April 

353,600 

261,000 

1,300 

261,000 

0 

0 

0 

430 

121,500 

May 

532,300 

261,000 

2,100 

261,000 

0 

0 

0 

447 

130,600 

June 

423,200 

261.000 

2,100 

261,000 

0 

0 

0 

389 

109,.500 

July 

221,600 

250,300 

1,700 

92,600 

0 

0 

10,700 

320 

30,800 

Aug. 

0 

23.000 

0 

0 

0 

0 

213,000 

0 

S.'pt. 

0 

22,400 

0 

0 

0 

0 

70,000 

0 

Oct. 

0 

0 

0 

0 

0 

0 

0 

(1 

Nov 

18,600 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,. 505,700 

8,.30O 

l,.3O2,6O0 

0 

0 

294,300 

416 

49,200 

338  WATER  RESOURCES  OF    CALIFORNIA. 

TABLE  9a  (Continued).     TEMPERANCE  FLAT 

WATER  AND  POWER  YIELD  BOTH  WITH  AND  WITHOUT 
Monthly  Summary  of  Computations 

("For  corresponding  yearly  sum 

Seasonal  irrigation  yield,  1,800,000  acre-feet.  (Supplemented  by  ground  water 
Height  of  dam  595  feet.     Capacity  of  reservoir  1,071,000  acre-feet. 


Run-off 

Withoiit  flood  control 

Irrigation 

Average 

Year  and 

at 

Stage  of 

draft  in 

Deficiency 

power 

Average 

month 

Friant 

reservoir 

aore-feet 

Power 

Waste 

in 

head 

power 

in 

at_ 

Tno 

Evapora- 

draft 

over 

irrigation 

through 

yield  in 

acre-feet 

beginning 

deduction 

tion  in 

through 

spillway 

supply 

period 

kilowatts 

of 

for  down- 

acre-feet 

turbines 

in 

in 

of 

fLoad 

month  in 

stream 

in  acre-feet 

acre-feet 

acre-feet 

operation 

factor= 

acre-feet 

prior 
rights) 

in 
feet 

1.00) 

1920 

Jan. 

26,900 

48,700 

0 

0 

0 

0 

0 

0 

Feb. 

28.900 

75,600 

47,000 

0 

0 

0 

0 

0 

Mar. 

101,000 

57,500 

119,000 

0 

0 

0 

0 

0 

April 

161,000 

39,500 

198,000 

0 

0 

0 

63.000 

0 

May 

407.000 

2.500 

259,600 

0 

8,400 

0 

1,400 

298 

2,600 

.lune 

327.000 

149,900 

261,000 

900 

261,000 

0 

0 

336 

95,700 

.July 

111,000 

215,000 

261,000 

1,400 

151,500 

0 

0 

320 

50,-500 

.^ug. 

4.5,400 

63,600 

108,900 

100 

0 

0 

152,100 

0 

Sept. 

29.200 

0 

29,200 

0 

0 

0 

206,800 

0 

Oct. 

37,000 

0 

37,000 

0 

0 

0 

56,000 

0 

Nov. 

44,600 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

43,000 

44,600 

0 

0 

0 

0 

0 

0 

1,362,000 

1,320,700 

2,400 

420.900 

0 

479,300 

329 

12,300 

1921 

.Ian. 

67,600 

87,600 

0 

0 

0 

0 

0 

0 

Feb. 

77,800 

155,200 

47,000 

0 

47,000 

0 

0 

3i7 

17,100 

Mar. 

162,000 

186,000 

119,000 

0 

119,000 

0 

0 

340 

42,900 

April 

189,000 

229,000 

261,000 

700 

261,000 

0 

0 

322 

90,700 

May 

323.000 

156,300 

261,000 

800 

201,000 

0 

0 

324 

88,400 

June 

407,000 

217,500 

261,000 

1,200 

261,000 

0 

0 

379 

110,100 

July 

1.55,000 

362,300 

261,000 

1,400 

261,000 

0 

0 

390 

109.900 

Aug. 

.51,600 

254,900 

261,000 

1,400 

151.500 

0 

0 

327 

52,000 

Sept. 

34,700 

44,100 

78,700 

100 

0 

0 

157,300 

0 

Oct. 

26,.30O 

0 

26,300 

0 

0 

0 

66,700 

0 

Nov. 

23.000 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

63,300 

23,000 

0 

0 

0 

0 

0 

0 

1,580,300 

1,576,000 

5,600 

1,361,500 

0 

224,000 

344 

42.700 

1922 

■Jan. 

67,600 

86,300 

0 

0 

0 

0 

0 

0 

Feb. 

96,100 

153,900 

47,000 

0 

47,000 

0 

0 

32  i 

17,400 

Mar. 

103,000 

203,000 

119,000 

0 

119,000 

0 

0 

328 

41,000 

April 

193,000 

187,000 

261,000 

700 

130,500 

0 

0 

308 

42,800 

May 

021,000 

118.300 

261,000 

700 

244,200 

0 

0 

367 

96.200 

June 

732,000 

477.600 

261,000 

1,900 

261,000 

0 

0 

512 

148,300 

July 

270,000 

946,700 

261,000 

3,600 

261,000 

0 

0 

565 

154.600 

Aug. 

84,800 

9,52,100 

261,000 

3,600 

261,000 

0 

0 

542 

150.000 

Sept. 

43,400 

772,300 

236,000 

2,200 

236,000 

0 

0 

498 

131. 00() 

Oct. 

31,900 

577,500 

93.000 

1,400 

93,000 

0 

0 

466 

46,900 

Nov. 

42,400 

515.000 

0 

900 

0 

0 

0 

0 

Dec. 
Total  or 
average 

91,600 

556,500 

0 

0 

0 

0 

0 

0 

2,376,800 

1,800,000 

15,000 

1,652,700 

0 

0 

443 

69,300 

1923 

Jan. 

69,500 

648,100 

0 

0 

0 

0 

0 

0 

Feb. 

70,000 

717,600 

47,000 

0 

47,000 

0 

0 

520 

29,000 

Mar. 

95,900 

740,600 

119,000 

0 

119,000 

0 

0 

513 

65,600 

April 

199,000 

717,500 

261,000 

1,600 

261,000 

0 

0 

500 

145,400 

May 

450,000 

6.53,900 

261.000 

2,000 

261,000 

0 

0 

513 

143,800 

June 

287.000 

840,900 

261,000 

2.800 

261,000 

0 

0 

538 

154,200 

July 

201,000 

864,100 

261,000 

3,300 

261,000 

0 

0 

539 

149,500 

Aug. 

72,600 

800,800 

261,000 

2.900 

261,000 

0 

0 

.507 

142,300 

Sept. 

.50,900 

609.500 

2.30.000 

1.900 

236.000 

0 

0 

453 

119.900 

t)ct. 

48,300 

422,500 

93,000 

1,200 

93,000 

0 

II 

420 

42.200 

Nov. 

33.000 

376.600 

0 

700 

0 

0 

0 

0 

Dec. 

27,700 

408,900 

0 

0 

0 

0 

0 

0 

Total  or 
average 

1,604,900 

1.800,000 

16,100 

1,800,000 

0 

0 

500 

82,900 

THE    CONTROL   OP    FLOODS   BY    RESERVOIKS. 


339 


RESERVOIR  ON  SAN  JOAQUIN  RIVER. 

FLOOD  CONTROL  BY  RESERVOIR  OPERATING  DIAGRAM. 
Carried  out  on  a  Daily  Basis. 

mary,  see  Table  9,  page  134.) 

supply  in  years  of  deficiency.     No  deduction  for  downstream  prior  rights.) 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.P.  =0.80. 


[Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Friant — rain-water  floods,  10 

700sec.-ft.; 

snow-water  floods,  14,20C 

sec.-ft. 

Maximum  rejervoir  space  required—  rain-water  floods,  133,000  ac.-ft. ;  snow-water  floods,  177,00C 

ac.-ft. 

Stage  of 
reservoir 

Irrigation 

Average 

draft  in 
acre-feet 

Power 

Release 

through 

flood 

control 
outlets  in 
acre-feet 

Waste 

Deficiency 

power 
head 

Average 
power 

Year  and 
month 

at 
beginning 

(no 
deddction 

Evapora- 
tion in 

draft 
through 

over 
spillway 

in 

irrigation 

supply 

in 
acre-feet 

through 
period 

yield  in 
kilowatts 

01 

month  in 
acre-feet 

for  down- 
stream 
prior 

acre-feet 

turbines 
in  acre-feet 

in 

acre-feet 

of 

operation 

in 

(Load 

factor  = 

1.00) 

rights) 

feet 

1920 

48,700 

0 

0 

0 

0 

0 

0 

0 

Jan. 

75,600 

47,000 

0 

0 

0 

0 

0 

0 

Fel). 

57,500 

119,000 

0 

0 

0 

0 

0 

0 

Mar. 

39,500 

198,000 

0 

0 

0 

0 

03,000 

0 

April 

2,500 

259,600 

0 

8,400 

0 

0 

1,400 

298 

2,600 

May 

149,900 

261,000 

900 

261,000 

0 

0 

0 

336 

95,700 

June 

215,000 

261,000 

1,400 

151,.500 

0 

0 

0 

320 

50,500 

July 

63,600 

108,900 

100 

0 

0 

0 

152,100 

'     0 

Aug. 

0 

29,200 

0 

0 

0 

0 

206,800 

0 

Sept. 

0 

37,000 

0 

0 

0 

0 

56,000 

0 

Oct. 

0 

0 

0 

0 

0 

0 

0 

0 

Nov. 

44,600 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,320,700 

2,400 

420,900 

0 

0 

479,300 

329 

12,300 

1921 

87,600 

0 

0 

0 

0 

0 

0 

0 

Jan. 

155,200 

47,000 

0  ■ 

47,000 

0 

0 

0 

3i7 

17,100 

Feb. 

186,000 

119,000 

0 

119,000 

0 

0 

0 

340 

42,900 

Mar 

229,000 

261,000 

700 

201,000 

0 

0 

0 

322 

90,700 

April 

156,300 

261,000 

800 

261,000 

0 

0 

0 

324 

88,400 

May 

217,500 

261,000 

1,200 

261,000 

0 

0 

0 

379 

110,100 

June 

362,300 

261,000 

1,400 

261,000 

0 

0 

0 

390 

109,900 

July 

254,900 

261,000 

1,400 

151,500 

0 

0 

0 

327 

52,000 

Aug. 

44,100 

78,700 

100 

0 

0 

0 

157,300 

0 

Sept 

0 

20,300 

0 

0 

0 

0 

66,700 

0 

Oct. 

0 

0 

0 

0 

0 

0 

0 

0 

Nov. 

23,000 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Total  nr 
average 

1,576,000 

5,600 

1,361,500 

0 

0 

224,000 

344 

42,700 

1922 

86,300 

0 

0 

0 

0 

0 

0 

0 

Jan. 

153,900 

47,000 

0 

47,000 

0 

0 

0 

32  i 

17.400 

Feb. 

203,000 

119,000 

0 

119,000 

0 

0 

0 

328 

41,000 

Mar 

187,000 

261,000 

700 

130,500 

0 

0 

0 

308 

42,800 

.\pril 

118,300 

261,000 

700 

244,200 

0 

0 

0 

367 

96,200 

May 

477,600 

261,000 

1,900 

261,000 

0 

0 

0 

512 

148,300 

June 

946,700 

261,000 

3,600 

261,000 

0 

0 

0 

565 

151,600 

July 

952,100 

261,000 

3,600 

261,000 

0 

0 

0 

542 

150,000 

Aug. 

772,300 

236,000 

2,200 

236,000 

0 

0 

0 

498 

131,000 

Sept. 

577,500 

93,000 

1,400 

93,000 

0 

0 

0 

466 

46,900 

Oct. 

515,000 

0 

900 

0 

0 

0 

0 

0 

Nov. 

,556,500 

0 

0 

0 

0 

0 

0 

0 

Dw. 

Total  or 
average 

1,800,000 

15,000 

1,652,700 

0 

0 

0 

443 

69,300 

1923 

648,100 

0 

0 

0 

0 

0 

0 

0 

Jan. 

717,600 

47,000 

0 

47,000 

0 

0 

0 

520 

29,000 

Feb. 

740,600 

119,000 

0 

119,000 

0 

0 

0 

513 

65,600 

Mar. 

717,500 

261,000 

1,600 

261,000 

0 

0 

0 

500 

145,400 

April 

653,900 

261,000 

2,000 

261,000 

0 

0 

0 

513 

143,800 

May 

840,900 

261,000 

2,800 

251,000 

0 

0 

0 

538 

154,200 

June 

864,100 

261,000 

3,300 

261,000 

0 

0 

0 

539 

149,,500 

July 

800,800 

261,000 

2,900 

261,000 

0 

0 

0 

507 

142,300 

Aug. 

609,500 

236,000 

1,900 

230,000 

0 

0 

0 

453 

119,900 

Sept. 

422,500 

03,000 

1,200 

03,000 

0 

0 

0 

420 

42,200 

Oct. 

376,600 

0 

700 

0 

0 

0 

0 

0 

Nov. 

408,900 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,800,000 

16,400 

1,800,000 

0 

0 

0 

500 

82,900 

340  WATER   RESOURCES  OF    CALIFORNIA. 

TABLE  9a  (Concluded).     TEMPERANCE  FLAT 

WATER  AND  POWER  YIELD  BOTH  WITH  AND  WITHOUT 
Monthly  Summary  of  Computations 

(For  corresponding  yearly  sum 

Seasonal  irrigation  yield  1,800,000  acre-feet.   (Supplemented  by  ground  water 
Height  of  dam  595  feet.     Capacity  of  reservoir  1,071,000  acre-feet. 


Run-oR 

at 
Friant 

Witho  It  flood  control 

Irrigation 

Average 

Year  and 
month 

Stage  of 
reservoir 

draft  in 
acre-feet 

Power 

Waste 

DeBciency 

power 
head 

Average 
power 

in 
acre-feet 

at 
beginning 

(no 
deduction 

Evapora- 
tion in 

draft 
through 

over 
spillway 

in 

irrigation 
supply 

through 
period 

yield  in 
kilowatts 

of 

for  down- 

acre-feet 

turbines 

in 

of 

(Load 

month  in 

stream 

in  acre-feet 

acre-feet 

in 
acre-feet 

operation 

factor= 

acre-feet 

prior 

in 

1.00) 

rights) 

feet 

1924 

Jan. 

26,900 

436,600 

0 

0 

0 

0 

0 

0 

Feb. 

22,600 

463,500 

47,000 

0 

47,000 

0 

0 

445 

24.100 

Mar. 

25,800 

439,100 

119,000 

0 

119,000 

0 

0 

419 

54.000 

.\pril 

8.3,300 

345,900 

261,000 

1,000 

261,000 

0 

0 

356 

102.600 

.May 

152,000 

167,200 

261,000 

800 

109,400 

0 

0 

304 

34,100 

.lune 

37,800 

57,400 

95,100 

100 

0 

0 

165,900 

0 

July 

20,600 

0 

20,600 

0 

0 

0 

240,400 

0 

Aug. 

16,200 

0 

16,200 

0 

0 

0 

244,800 

0 

S3pt. 

12,700 

0 

12,700 

0 

0 

0 

223.300 

0 

Oct. 

17,700 

0 

11,700 

0 

0 

0 

81,300 

n 

Nov. 

27,800 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

28,700 

27,800 

0 

0 

0 

0 

0 

0 

466,100 

844,300 

1,900 

536,400 

0 

955,700 

394 

17,800 

1925 

Jan. 

27,100 

56,500 

0 

0 

0 

0 

0 

0 

Feb. 

77,800 

83,600 

47,000 

0 

0 

0 

0 

0 

Mar. 

94,700 

114,400 

119,000 

0 

0 

0 

0 

0 

.\pril 

196,000 

90,100 

261,000 

400 

0 

0 

0 

0 

May 

364,000 

24,700 

261,000 

200 

0 

0 

0 

0 

June 

281,000 

127,500 

261,000 

800 

60,900 

0 

0 

298 

19.000 

July 

151,000 

146,700 

261,000 

1.100 

50,500 

0 

0 

298 

15,300 

Aug. 

65,800 

35,600 

101,300 

100 

0 

0 

159,700 

0 

Sept. 

37.100 

0 

37,100 

0 

0 

0 

198,900 

0 

Oct. 

39,200 

0 

39,200 

0 

0 

0 

53,800 

0 

Nov. 

3?,900 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

40,800 

38,900 

0 

0 

0 

0 

0 

0 

1,413,400 

1,387,600 

2,600 

111,400 

0 

412,400 

298 

2,900 

Total  for 

18-year 

period, 

1908-1926 

32,675,600 

2a984,500 

225,000 

25,008,000 

3,970,400 

3,415,500 

Average 

for 

18-year 

period, 

1908-1926 

1,815.300 

1,610,300 

12.500 

1,389,300 

220,600 

189,700 

490 

62.000 

THE   CONTROL   OF    FLOODS   BY    RESERVOIRS. 


341 


RESERVOIR  ON  SAN  JOAQUIN  RIVER. 

FLOOD  CONTROL  BY  RESERVOIR  OPERATING  DIAGRAM. 
Carried  out  on  a  Daily  Basis. 

mary,  see  Table  9,  page  134.) 

supply  in  years  of  deficiency.     No  deduction  for  downstream  prior  rights.) 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.P.  =  0.80. 


Coordinated  with  flood  control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Friant — rain-water  flond.s,  10,700  see.-ft.: 

snow-water  floods.  14,200  sec.-ft. 

Maximum  re3erv>.ir 

space  reiuired— rain-water  floods,  133,000  ac.-ft.; 

now-water  floods,  177,000  ac.-ft. 

Rtage  of 
reservoir 

at 
beginning 

Irrigation 

Average 

draft  in 
acre-feet 

Power 

Release 

through 

flood 

control 
outleta  in 
aere-feet 

Waste 

Deficiency 

power 
head 

Average 
power 

Year  and 
month 

(no 
deduction 

Evapora- 
tion in 

draft 
through 

over 
spillway 

in 

irrigation 

supply 

in 
acre-feet 

through 
period 

yield  in 
kilowatts 

of 
month  in 
acre-feet 

for  down- 
stream 
prior 

acre-feet 

turbines 
in  acre-feet 

in 
acre-feet 

of 

operation 

in 

(Load 

factor  — 

1.00) 

rights) 

feet 

1924 

436,600 

0 

0 

0 

0 

0 

0 

0 

Jan. 

463,500 

47,000 

0 

47,000 

0 

0 

0 

445 

24,100 

Feb 

439,100 

119,000 

0 

119,000 

0 

0 

0 

419 

54,000 

Mar 

345,900 

261,000 

1,000 

261,000 

0 

0 

0 

356 

102,600 

April 

167,200 

261,000 

800 

109,400 

0 

0 

0 

304 

34,100 

May 

57,400 

95,100 

100 

0 

0 

0 

165,900 

0 

,Iune 

0 

20,600 

0 

0 

0 

0 

240,400 

0 

July 

0 

16,200 

0 

0 

0 

0 

244,800 

0 

Aug. 

0 

12,700 

0 

0 

0 

0 

2.33,300 

0 

Sept. 

0 

11,700 

0 

0 

0 

0 

81,300 

0 

Oct. 

0 

0 

0 

0 

0 

0 

0 

0 

Nov. 

27,800 

0 

0 

0 

0 

« 

0 

0 

Dec. 
Total  or 
average 

844,300 

1,900 

536,400 

0 

0 

955,700 

394 

17,800 

1925 

56,500 

0 

0 

0 

0 

0 

0 

0 

Jan. 

83,600 

47,000 

0 

0 

0 

0 

0 

0 

Feb 

114,400 

119,000 

0 

0 

0 

0 

0 

0 

Mar. 

90,100 

261,000 

400 

0 

0 

0 

0 

0 

April 

24,700 

261,000 

200 

0 

0 

0 

0 

0 

May 

127,,50O 

261,000 

800 

60,900 

0 

0 

0 

298 

19,000 

June 

146,700 

261,000 

1,100 

50,500 

0 

0 

0 

298 

15,300 

July 

35,600 

101,300 

100 

0 

0 

0 

159,700 

0 

Aug. 

0 

37,100 

0 

0 

0 

0 

198,900 

0 

Sept. 

0 

39,200 

0 

0 

0 

0 

53,800 

0 

Oct. 

0 

0 

0 

0 

0 

0 

0 

0 

Nov. 

38,900 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,387,600 

2,600 

111,400 

0 

0 

412,400 

298 

2,900 

Total  for 

18-year 

period. 

28,98^,500 

219,800 

25,010,400 

3,530,700 

442,500 

3,415,500 

1908-1926 

Average 
for 

18-year 
period. 

1,610,300 

12,200 

1,389.500 

196,100 

24,600 

189,700 

484 

61,400 

1908-1926 

342 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  10a      TEMPERANCE  FLAT  RESER 

COMPARISON  OF  WATER  AND  POWER  YIELD 

Monthly  Summary  of  Computations 

(For  corresponding  yearly  sum 

Seasonal  irrigation  yield  1,800,000  acre-feet.    (Supplemented  by  ground  water 

Height  of  dam  595  feet.     Capacity  of  reservoir  1,071,000  acre-feet. 


Flood 

control  by 

reservoir  operating  diagram 

Maximum  controlled  3ow  at  Friant — rain-water  floods,  10,700  sec.-ft.; 

snow-water  floods,  14,200  sec.-ft. 

Maximum  reser\-oir  space  required — rair 

-water  floods,  133,000 

ic.-ft.; 

snow-water  floods,  177,000  ac.-ft. 

Run-off 

at 

Irrigation 

Year  and 
month 

Friant 
in 

Stage  of 

draft 
in 

Power 

Release 

Waste 

Deficiency 

.\verage 
power 

.\verage 

acre-feet 

reservoir 
at 

beginning 

of 
month  in 
acre-feet 

acre-feet 

Evapora- 
tion in 
acre-feet 

draft 

through 

in 

head 

power 
yield  in 
kilowatts 

(Load 
factor= 

1.00) 

(no 
deduction 
for  down- 
stream 
prior 

through 
turbines 

in 
acre-feet 

flood 

control 

outlets  in 

acre-feet 

over 
spillway 

in 
acre-feet 

irrigation 
supply 

in 
acre-feet 

through 

period 

of 

operation 

in  feet 

rights) 

1908 

Jan. 

53,100 

797,100 

0 

0 

0 

0 

0 

0 

0 

Keb. 

58,100 

850,200 

47.000 

0 

47,000 

0 

0 

0 

548 

29,200 

Mar. 

120,000 

861,300 

119.000 

0 

119,000 

0 

0 

0 

543 

68,400 

.\pril 

199,000 

862,300 

261,000 

1,700 

261,000 

0 

0 

0 

5.30 

152,400 

May 

219,000 

798,600 

261,000 

2,200 

261,000 

0 

0 

0 

522 

145,800 

June 

176,000 

754,400 

261,000 

2.600 

261,000 

0 

0 

0 

507 

146.900 

July 

119,000 

666.800 

261,000 

2.800 

261,000 

0 

0 

0 

478 

135.100 

Aug. 

73,200 

522,000 

261,000 

2.300 

261,000 

0 

0 

0 

429 

121.100 

Sept. 

39,000 

331,900 

236,000 

1.300 

228,100 

0 

0 

0 

347 

86.800 

Oct. 

23,900 

133,600 

93,000 

600 

0 

0 

0 

0 

0 

Nov. 

16,200 

63,900 

0 

200 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

18,500 

79,900 

0 

0 

0 

0 

0 

0 

0 

1,115.000 

1,800,000 

13,700 

1,699,100 

0 

0 

0 

488 

73,800 

1909 

Jan. 

277.000 

98,400 

0 

0 

0 

0 

0 

0 

0 

Feb. 

183,000 

375,400 

47,000 

0 

47,000 

0 

0 

0 

438 

24,700 

Mar. 

133,000 

511.400 

119,000 

0 

119,000 

0 

0 

0 

460 

59.300 

April 
May 

352,000 

525,400 

261,000 

1,300 

261,000 

0 

0 

0 

459 

134.200 

646,000 

615,100 

261,000 

1.900 

266.400 

86,700 

0 

0 

529 

150,300 

June 

827,000 

906,100 

261,000 

2,900 

273.000 

484,800 

0 

0 

553 

164,400 

July 

309,000 

972,400 

261,000 

3,600 

263.900 

34.400 

0 

0 

568 

150,600 

Aug. 

78,100 

979,500 

261,000 

3.400 

261.000 

0 

0 

0 

543 

1.50,300 

Sept. 

37,000 

793,200 

236,000 

2,300 

236.000 

0 

0 

0 

500 

131,400 

Oct. 

25,000 

591,900 

93,000 

1,500 

93.000 

0 

0 

0 

468 

47,200 

Nov. 

49,600 

522,400 

0 

900 

0 

0 

0 

0 

0 

Dec. 

220,000 

571,100 

0 

0 

0 

0 

0 

0 

0 

Total  or 
average 

3,136,700 

1,800,000 

17,800 

1,820,300 

C05.900 

0 

0 

503 

85,100 

1910 
Jan. 

188,000 

791,100 

0 

0 

0 

0 

0 

0 

0 

Feb. 

86,600 

979,100 

47.000 

0 

87,600 

900 

0 

0 

567 

57,600 

Mar. 

188,000 

977,200 

119,000 

0 

123,200 

0 

0 

0 

574 

73,800 

April 
May 

375,000 

1,042,000 

261,000 

1,900 

262,200 

33,800 

66,500 

0 

576 

162.600 

475,000 

1,052,600 

261,000 

2,700 

280,900 

328.800 

0 

0 

556 

164.400 

June 

237,000 

915,200 

261,000 

2,900 

263,300 

37.800 

0 

0 

547 

157.400 

July 

99,600 

848,200 

261,000 

3,300 

261,000 

0 

0 

0 

520 

145.200 

Aug. 

39,600 

683,500 

261,000 

2,700 

261,000 

0 

0 

0 

469 

132.700 

Sept. 

51,700 

459,400 

236,000 

1,600 

236,000 

0 

0 

0 

398 

104.900 

Oct. 

29,600 

273,500 

93.000 

900 

93,000 

0 

0 

0 

357 

35,500 

Nov. 

24,000 

209.200 

0 

500 

0 

0 

0 

0 

0 

Dee. 
Total  or 
average 

31,400 

232,700 

0 

0 

0 

0 

0 

0 

0 

1,825,500 

1,800,000 

16,500 

1,868,200 

401,300 

66,500 

0 

506 

86,200 

1911 

Jan. 

239,000 

264,100 

0 

0 

0 

0 

0 

0 

0 

Feb. 

207,000 

503,100 

47,000 

0 

47,000 

0 

0 

0 

489 

27.500 

Mar. 

336,000 

663.100 

119,000 

0 

119,000 

0 

0 

0 

525 

66.700 

April 
May 

425,000 

880.100 

261,000 

1.800 

261,000 

0 

0 

0 

561 

158,900 

571,000 

1.042.300 

261,000 

2.600 

280,000 

4.30,500 

0 

0 

557 

164,000 

Juno 

946,000 

900.200 

261,000 

2.900 

272.300 

541,900 

0 

0 

555 

164,400 

July 

593,000 

1.029.100 

261,000 

3.700 

273.100 

203,700 

74,600 

0 

574 

163.300 

Aug. 

116,000 

1.067.000 

261,000 

3.500 

261.000 

0 

0 

0 

569 

15.S.200 

Sept. 

45.500 

918.500 

236,000 

2.400 

236.000 

0 

0 

0 

532 

138.200 

Oct. 

32,300 

725.600 

93,000 

1,600 

93.000 

0 

0 

0 

507 

50,700 

Nov. 

28,000 

663.300 

0 

1,000 

0 

0 

0 

0 

0 

Deo. 
Total  or 
average 

23,400 

690.300 

0 

0 

0 

0 

0 

0 

0 

3,562,200 

1,800,000 

19,500 

1.842,400 

1.176,100 

74,600 

0 

542 

91,000 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 
VOIR  ON  SAN  JOAQUIN  RIVER. 


348 


FOR  TWO  METHODS  OF  FLOOD  CONTROL. 
Carried  out  on  a  Daily  Basis. 

mary,  see  Table  10,  page  13b.) 

supply  in  years  of  deficiency.     No  deduction  for  downstream  prior  rights. ) 

Installed  capacity  of  power  plant  400,000  k.v.a.     P. F.  =  0.80. 


Flood  control,  holding  maximum  space  required  (rain-water  floods,  133,000  ac.-ft.; 

siow-water  floods,  177,000  ac.-ft.)  In  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Friant— rain-wa 

erflaoda,  10 

,700sec.-ft.; 

snow-water 

floods.  14,200  sec.-ft. 

Irrigation 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

draft 

in 

acre-feet 

Evapora- 
tion in 
acre-leet 

Power 
draft 

Release 
through 

Waste 

Deficiency 
in 

.\verage 
power 
head 

.\verage 
power 

yield  in 

kilowatts 
(Load 

factor= 
1.00) 

Year  and 
month 

(no 
deduction 
for  down- 
stream 
prior 

through 
turbines 

in 
acre-tee  t 

flood 

control 

outlets  in 

acre-feet 

over 
spillway 

in 
acre-feet 

irrigation 
sjpply 

in 
acre-feet 

through 

period 

of 

operation 
in  feet 

rights) 

1908 

797,100 

0 

0 

0 

0 

0 

0 

0 

Jan. 

850,200 

47,000 

0 

47,000 

0 

0 

0 

548 

29,200 

Feb. 

861,300 

119,000 

0 

119,000 

0 

0 

0 

543 

68,400 

Mar. 

862,300 

261,000 

1,700 

261,000 

0 

0 

0 

530 

152,400 

April 

798,600 

261,000 

2.200 

261,000 

0 

0 

0 

.522 

145,800 

May 

754,400 

261,000 

2,600 

261,000 

0 

0 

0 

507 

146,900 

June 

666,800 

261,000 

2.800 

261,000 

0 

0 

0 

478 

135,100 

July 

522,000 

261,000 

2..300 

261,000 

0 

0 

0 

429 

121,100 

Aug. 

331,900 

236,000 

1,300 

228,100 

0 

0 

0 

347 

86,800 

Sept. 

133,600 

93,000 

600 

0 

0 

0 

0 

0 

Oct. 

03,900 

0 

200 

0 

0 

0 

0 

0 

Nov. 

79,900 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,800,000 

13,700 

1,699,100 

0 

0 

0 

488 

73,800 

1909 

98,400 

0 

0 

0 

0 

0 

0 

0 

Jan. 

375,400 

47,000 

0 

47,000 

0 

0 

0 

438 

24,700 

Feb. 

511,400 

119,000 

0 

119,000 

0 

0 

0 

460 

59,300 

Mar. 

525,400 

261,000 

1,300 

261,000 

0 

0 

0 

459 

134.200 

April 

615,100 

261,000 

1,900 

269,000 

96,200 

0 

0 

527 

151,500 

May 

894,000 

261,000 

2,900 

274,800 

549,.300 

0 

0 

548 

164,400 

June 

894,000 

251,000 

3,400 

272,200 

79,000 

0 

0 

544 

156,900 

July 

848.400 

261,000 

3,100 

261,000 

0 

0 

0 

516 

144,400 

Aug. 

662,400 

236,000 

2,000 

236.000 

0 

0 

0 

466 

123,300 

Sept. 

461,400 

93,000 

1,200 

93,000 

0 

0 

0 

430 

43,300 

Oct. 

392,200 

0 

700 

0 

0 

0 

0 

0 

Nov. 

441,100 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,800,000 

16,500 

1,833,000 

624,.500 

0 

0 

488 

83,700 

1910 

661,100 

0 

0 

0 

0 

0 

0 

0 

Jan. 

849,100 

47,000 

0 

47,000 

0 

0 

0 

552 

30,400 

Feb. 

888,700 

119,000 

0 

138,700 

0 

0 

0 

555 

81,200 

Mar. 

938,000 

261,000 

1,800 

262,400 

76,500 

0 

0 

558 

159,000 

.\pril 

972,300 

261,000 

2,.500 

285,500 

265,300 

0 

0 

544 

164,400 

May 

894,000 

261,000 

2,900 

263,600 

35,700 

0 

0 

542 

150,700 

June 

828,800 

261,000 

3,300 

261,000 

0 

0 

0 

514 

144,000 

July 

664,100 

261,000 

2,600 

261,000 

0 

0 

0 

463 

131,000 

Aug. 

440,100 

236,000 

1,600 

236,000 

0 

0 

0 

396 

104,200 

Sept. 

254,200 

93,000 

800 

93,000 

0 

0 

0 

344 

34,000 

Oct. 

190.000 

0 

500 

0 

0 

0 

0 

0 

Nov. 

213,500 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Tnt'il  nr 

1,800,000 

16,000 

1,848,200 

377,500 

0 

0 

496 

83,900 

1  UUll   Ul 

average 
1911 

244,900 

0 

0 

0 

0 

0 

0 

0 

Jan. 

483,900 

47,000 

0 

47,000 

0 

0 

0 

484 

27,200 

Feb. 

643,900 

119,000 

0 

119,000 

0 

0 

0 

.520 

66,.30O 

Mar. 

860,900 

261,000 

1,700 

262,400 

76,500 

0 

0 

555 

158,.500 

April 

945,300 

261,000 

2,500 

286,000 

333,800 

0 

0 

543 

164,400 

May 

894,000 

261,000 

2,900 

272,700 

540,100 

0 

0 

554 

164,400 

June 

1,024,300 

261,000 

3,700 

270,000 

287,200 

0 

0 

568 

160,400 

July 

1,056,400 

261,000 

3,500 

261,000 

0 

0 

0 

566 

154,800 

Aug. 

907,900 

236,000 

2,400 

236,000 

0 

0 

0 

529 

137,500 

Sept. 

715,000 

93,000 

1,600 

93,000 

0 

0 

0 

504 

50,400 

Oct. 

652,700 

0 

1,000 

0 

0 

0 

0 

0 

Nov. 

679,700 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

1.800,000 

19,300 

1,847,100 

1,237,600 

0 

0 

536 

90,600 

344  WATElt   RESOURCES   OF    CALIFORNIA. 

TABLE  10a  (Continued).     TEMPERANCE  FLAT 

COMPARISON  OF  WATER  AND  POWER  YIELD 
Monthly  Summary  of  Computations 

(For  corresponding  yearly  sum 

Seasonal  irrigation  yield  1,800,000  acre-feet.   (Supplemented  by  ground  water 
Height  of  dam  595  feet.     Capacity  of  reservoir  1,071,000  acre-feet. 


Flood 

control  by 

reservoir  operating  diagram 

Maximum  control 

cd  flow  at  Friant — rain-witer  floods.  10,700  see.-ft.; 

snow-wate 

fljcds,  14,21)0  sec. -It. 

Maximum  reservoir  space  required — rait 

-water  floods.  133,000 

ac.-ft.; 

IlllM-off 

snow-water 

floods,  177 

,000  ac.-ft. 

at 

Irrigation 

Year  and 
month 

Friant 
in 

Stage  of 

draft 
in 

Power 

Release 

Wa.^te 

Deficiency 

Average 
power 

Average 

acre-feet 

reservoir 

at 
beginning 

acre-feet 

Evapora- 

draft 

through 

in 

head 

power 

(no 

through 

flood 

over 
spillway 

irrigation 

through 

yield  in 

deduction 

tion  in 
ac.-e-feet 

turbines 

control 

supply 

period 

kilowatts 

01 

montti  in 
acre-feet 

for  down- 
stream 
prior 

in 
acre-feet 

outlets  in 
acre-feet 

in 

acre-feet 

in 
acre-feet 

of 

operation 

in  feet 

(Load 

factor^^ 

1.00) 

rights) 

1912 

Jan. 

30,100 

713,700 

0 

0 

0 

0 

0 

0 

0 

Feb. 

26,600 

743,800 

47,000 

0 

47,000 

0 

0 

0 

52i 

28,000 

Mar. 

.55,200 

723,400 

119,000 

0 

119,000 

0 

0 

0 

505 

64,700 

April 

75,000 

659,600 

261,000 

1,500 

261,000 

0 

0 

0 

468 

136,700 

May 

255,000 

472,100 

261,000 

1,600 

261,000 

0 

0 

0 

431 

121,800 

June 

368,000 

464,500 

261,000 

1,900 

261,000 

0 

0 

0 

472 

137,900 

July 

95,300 

569,600 

261,000 

2.600 

261,000 

0 

0 

0 

445 

125,800 

Aug. 

38,000 

401,300 

261,000 

1,900 

261,000 

0 

0 

0 

367 

102,700 

Sept. 

22,400 

176,400 

198,100 

700 

39,300 

0 

0 

37,900 

305 

12,800 

Oct. 

17,800 

0 

17,800 

0 

0 

0 

0 

75,200 

0 

Nov. 

20,300 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

20,000 

20,300 

0 

0 

0 

0 

0 

0 

0 

1,023,700 

1,686,900 

10,200 

1,510,300 

0 

0 

113,100 

454 

60,900 

1913 

Jan. 

22,100 

40,300 

0 

0 

0 

0 

0 

0 

0 

Feb. 

25,700 

62,400 

47,000 

0 

0 

0 

0 

0 

0 

Mar. 

38,200 

41,100 

79,300 

0 

0 

0 

0 

39,700 

0 

April 

95,800 

0 

95.800 

0 

0 

0 

0 

165,200 

0 

May 

247,000 

0 

219,200 

0 

0 

0 

0 

41,800 

0 

June 

170,000 

27,800 

197,700 

100 

0 

0 

0 

63,300 

0 

July 

102,000 

0 

102,000 

0 

0 

0 

0 

159,000 

0 

Aug. 

68.900 

0 

68,900 

0 

0 

0 

0 

192.100 

0 

Sept. 

40,600 

0 

40,600 

0 

0 

0 

0 

195.400 

0 

Oct. 

12,800 

0 

12,800 

0 

0 

0 

0 

802,000 

0 

Nov. 

22,300 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
avrrage 

28,700 

22,300 

0 

0 

0 

0 

0 

0 

0 

874,100 

863,300 

100 

0 

0 

0 

930,700 

0 

0 

1914 

Jan. 

259,000 

51,000 

0 

0 

0 

0 

0 

0 

0 

Feb. 

14.5,000 

310,000 

47,000 

0 

47,000 

0 

0 

0 

404 

22,800 

Mar. 

234,000 

408,000 

119,000 

0 

119,000 

0 

0 

0 

439 

56,600 

April 
May 

395,000 

523,000 

261,000 

1,300 

261,000 

0 

0 

0 

475 

138.800 

577,000 

655,700 

261.000 

2,000 

264,300 

66,800 

0 

0 

519 

146,800 

June 

607.000 

899,600 

261,000 

2,900 

275,100 

2t)4,900 

0 

0 

547 

164,400 

July 

392,000 

963,700 

261,000 

3,600 

265,000 

26,200 

0 

0 

574 

158.600 

Aug. 

142,000 

1,060,900 

261,000 

3,.500 

261,000 

0 

0 

0 

573 

1.56,100 

Sopt. 

53,900 

938,400 

236,000 

2,500 

236,000 

0 

0 

0 

537 

139,000 

Oct. 

40,300 

753,800 

93,000 

1,700 

93,000 

0 

0 

0 

513 

51,200 

Nov. 

30,500 

699,400 

0 

1,100 

0 

0 

0 

0 

0 

Dec. 
ToUl  or 
averaiEC 

20,600 

728,800 

0 

0 

0 

0 

0 

0 

0 

2,905,300 

1,800,000 

18,600 

1,821,400 

357,900 

0 

0 

510 

86,400 

1915 

Jan. 

38,2(X) 

758.400 

0 

0 

0 

0 

0 

0 

0 

Feb. 

90,000 

796,600 

47,000 

0 

47,000 

0 

0 

0 

537 

29,600 

Mar. 

124,000 

839,600 

119,000 

0 

119,000 

0 

0 

0 

.537 

67.900 

.^i)ril 
May 

246,000 

844,600 

201,000 

1,700 

261,000 

0 

0 

0 

.532 

152,800 

381,000 

827,900 

261,000 

2„300 

264,100 

44,300 

0 

0 

538 

151,100 

June 

580,000 

898,200 

261,000 

2.900 

275,200 

241. .300 

0 

0 

547 

164.400 

July 

287,000 

964,800 

261,000 

3,600 

263,300 

2,100 

0 

0 

568 

1,56,500 

Aug. 

70.100 

082,800 

201,000 

3.400 

261,000 

0 

0 

0 

545 

1.50,700 

Sept. 

44,300 

788.500 

236,000 

2,300 

236,000 

0 

0 

0 

500 

131,400 

Oct, 

26.700 

594,500 

93,000 

1,500 

93,000 

0 

0 

0 

466 

47,000 

Nov. 

23.400 

62»«,700 

0 

900 

0 

0 

0 

0 

0 

Dec. 
Total  or 

37.900 

549,200 

0 

0 

0 

0 

0 

0 

0 

average 

1,054,600 

1,800,000 

18,600 

1,819,600 

287,700 

0 

0 

530 

87,800 

THE    CONTROL    OF    FLOODS    BY    RESERVOIRS. 


345 


RESERVOIR  ON  SAN  JOAQUIN  RIVER. 

FOR  TWO  METHODS  OF  FLOOD  CONTROL. 
Carried  out  on  a  Daily  Basis. 

mary,  see  Table  10,  page  13b.) 

supply  in  years  of  deficiency.     No  deduction  for  downstream  prior  rights.) 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.F.  =0.80. 


Flood  control,  holding  maximum  space  retiulred  (rair-water  floods,  133.000  ac.  ft.; 

snov 

-water  fiooJs,  177.000  ac.-/t.)  in  reserve  through 

)ut  flood  season 

Maximvira  controlled  flow  at  Friaiit — raiii-witor  floods,  10, 

700soc.-ft.; 

snow-water  floutls,  14,201 

sec.-ft. 

Irrigation 

draft 

Average 

Average 

Year  ami 

Stage  ol 

in 

Power 

Release 

W-iste 

over 

spillway 

in 
acre-feet 

Deficiency 

power 

month 

reservoir 

at 
beginning 

of 
month  in 
anre-feet 

acre-feet 

(no 
deduction 
for  down- 
stream 
prior 

Evapora- 
tion in 
acre-feet 

draft 
through 
turbines 

in 
acre-feet 

through 

fljod 

control 

outlets  in 

acre-feet 

in 

irrigation 

supply 

in 
acre-ieet 

head 

through 

period 

of 

operation 

in  feet 

power 
yield  in 
kilowatts 

(Load 
factor -^ 

1.00) 

rights) 

1912 

703,100 

0 

0 

0 

0 

0 

0 

0 

.Ian. 

733,200 

47,000 

0 

47,000 

0 

0 

0 

sis 

27,900 

Feb. 

712,800 

119,000 

0 

119,000 

0 

0 

0 

502 

64,400 

Mar. 

649,000 

261,000 

1,500 

261,000 

0 

0 

0 

464 

135,600 

April 

461,500 

261,000 

1,600 

261,000 

0 

0 

0 

427 

120,600 

May 

453,900 

261,000 

1,900 

261,000 

0 

0 

0 

468 

136,800 

,fune 

559,000 

261,000 

2,500 

201,000 

0 

0 

0 

441 

124,700 

July 

390,800 

261,000 

1,900 

261,000 

0 

0 

0 

361 

101,100 

Aug. 

165,900 

187,700 

600 

23,600 

0 

0 

48,300 

302 

7,500 

Sept. 

0 

17,800 

0 

0 

0 

0 

75,200 

0 

Oct. 

0 

0 

0 

0 

0 

0 

0 

0 

Nov. 

20,300 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,676,500 

10,000 

1,494,600 

0 

0 

123,500 

4.54 

59,900 

1913 

40,300 

0 

0 

0 

0 

0 

0 

0 

Jan. 

62.400 

47.000 

0 

0 

0 

0 

0 

0 

Feb. 

41,100 

79,300 

0 

0 

0 

0 

39,700 

0 

Mar. 

0 

95,800 

0 

0 

0 

0 

165,200 

0 

April 

0 

219,200 

0 

0 

0 

0 

41,800 

0 

May 

27,800 

197,700 

100 

0 

0 

0 

63,300 

0 

June 

0 

102,000 

0 

0 

0 

0 

159,000 

0 

July 

0 

68,900 

0 

0 

0 

0 

192,100 

0 

Aug. 

0 

40,600 

0 

0 

0 

0 

195,400 

0 

Sept. 

0 

12,800 

0 

0 

0 

0 

80,200 

0 

Oct. 

0 

0 

0 

0 

0 

0 

0 

0 

Nov. 

22,300 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

863,300 

100 

0 

0 

0 

936,700 

0 

0 

1914 

51,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

310,000 

47,000 

0 

47,000 

0 

0 

0 

404 

22,800 

Feb. 

408,000 

119.000 

0 

119,000 

0 

0 

0 

439 

56,600 

Mar. 

5'i3,000 

261,090 

1,300 

261,000 

0 

0 

0 

475 

138,800 

.\pril 

655,700 

261,000 

2,000 

265,100 

71,600 

0 

0 

519 

147,200 

May 

894,000 

261,000 

2,900 

277,100 

327.000 

0 

0 

542 

164,400 

June 

894,000 

261,000 

3,400 

272,900 

98,800 

0 

0 

547 

157,900 

July 

910,900 

261,000 

3,200 

261.000 

0 

0 

0 

541 

149,700 

Aug. 

788,700 

236,000 

2,.300 

236,000 

0 

0 

0 

502 

131,900 

Sept. 

604, .300 

93,000 

1,500 

93,000 

0 

0 

0 

474 

47,800 

Oct. 

550,100 

0 

900 

0 

0 

0 

0 

0 

Nov. 

579,700 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,800,000 

17,500 

1,832,100 

497,400 

0 

0 

495 

85,000 

1915 

609,300 

0 

0 

0 

0 

0 

0 

0 

Jan. 

647,500 

47,000 

0 

47,000 

0 

0 

0 

502 

28,100 

Feb. 

690.500 

119,000 

0 

119,000 

0 

0 

0 

503 

64,400 

Mar. 

695,500 

261,000 

1.500 

26 1.000 

0 

0 

0 

497 

144,600 

,\pril 

679,000 

261.000 

2,000 

261,000 

0 

0 

0 

50ti 

142,100 

May 

797.000 

261,000 

2.700 

273,200 

213,100 

0 

0 

541 

1 6 1.900 

June 

894.000 

261,000 

3.400 

271,800 

45.300 

0 

0 

545 

15t:..900 

July 

860,500 

261,000 

3.100 

261,000 

0 

0 

0 

529 

147,200 

Aug. 

666,500 

236,000 

2,000 

236,000 

0 

0 

0 

468 

123,800 

Sept. 

472,800 

93,000 

1,200 

93,000 

0 

0 

0 

433 

43,.500 

Oct. 

405,300 

0 

800 

0 

0 

0 

0 

0 

Nov. 

427,900 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 

1,800,000 

16,700 

1,823,000 

258,400 

0 

0 

503 

84,000 

average 

22^52411 


346 


WATER   RESOURCES  OF    CALIFORNIA. 


TABLE  10a  (Continued).     TEMPERANCE  FLAT 

COMPARISON  OF  WATER  AND  POWER  YIELD 

Monthly  Summary  of  Computations 

(For  corresponding  yearly  sum 

Seasonal  irrigation  yield  1,800,000  acre-feet.   (Supplemented  by  ground  water 

Height  of  dam  595  feet.     Capacity  of  reservoir  1,071,000  acre-feet. 


riood 

control  by  reservoir  operating  diagram 

Maximum  controlled  flow  at  Friaiit— rai 

1-water  floods,  10,700 

ec.-ft.; 

snow-water  floods,  14.200  sec.-ft. 

Maximum  reservoir  space  re:iuired — rair 

-water  floods,  133,000 

ac.-ft.; 

snow-water  floods,  17 

'.OOOac.-ft. 

Run-off 

at 

Irrigation 

Year  and 

Fnant 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

draft 

Average 

.\veragc 
power 

yield  in 

kilowatts 
(Load 

factor— 
1.00) 

month 

in 
acre-feet 

in 
acre-feet 

Evapora- 
tion in 
acre-feet 

Power 
draft 

Release 
through 

Waste 

Deficiency 
in 

pawer 
head 

(no 
deduction 
for  down- 
stream 
prior 

through 
turbines 

in 
acre-feet 

flood 
control 
outlets  in 
acre-feet 

over 
spillway 

in 
acre-feet 

irrigation 
supply 

in 
acre-feet 

through 

period 

of 

operation 

in  feet 

rights) 

1916 

Jan. 

173,000 

587,100 

0 

0 

0 

0 

0 

0 

0 

Feb. 

142,000 

760,100 

47,000 

0 

47,000 

0 

0 

0 

5.32 

28,400 

Mar. 

338,000 

855,100 

119,000 

0 

122,100 

0 

0 

0 

562 

72,000 

April 

477,000 

1,071,000 

261,000 

2,000 

264.300 

0 

210.700 

0 

579 

164,400 

May 

552.000 

1,071,000 

261,000 

2.700 

280,100 

417.600 

21,500 

0 

558 

164.400 

June 

572,000 

901,100 

261.000 

2,900 

274,000 

226,600 

0 

0 

549 

164,300 

July 

289,000 

969,600 

261,000 

3.600 

261.000 

0 

0 

0 

569 

l.i5.400 

Aug. 

91,000 

994,000 

261,000 

3.400 

261,000 

0 

0 

0 

551 

151,700 

Sept. 

44,900 

820,600 

236.000 

2..300 

236.000 

0 

0 

0 

509 

133.300 

Oct. 

63,900 

627,200 

93,000 

1..500 

93,000 

0 

0 

0 

486 

48,900 

Nov. 

38,900 

596,600 

0 

1,000 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

45,300 

634,500 

0 

0 

0 

0 

0 

0 

0 

2,827,000 

1,800,000 

19,400 

1,838,500 

644,200 

232,200 

0 

544 

90,.300 

1917 

Jan. 

47.500 

670,800 

0 

0 

0 

0 

0 

0 

0 

Feb. 

129,000 

727,300 

47.000 

0 

47,000 

0 

0 

0 

519 

28.900 

Mar. 

108,000 

809,300 

119,000 

0 

119,000 

0 

0 

0 

531 

67,300 

April 

226,000 

798,300 

261,000 

1.700 

261.000 

0 

0 

0 

518 

149,700 

May 

373.000 

701,600 

261.000 

2,200 

261.000 

0 

0 

0 

.530 

147.400 

June 

579,000 

871,400 

261,000 

2,800 

262,900 

57,600 

56.100 

0 

569 

161.400 

July 

222,000 

1,071,000 

261,000 

3.800 

264,200 

0 

13,100 

0 

579 

159,100 

Aug. 

72,600 

1,011.900 

261.000 

3.400 

261,000 

0 

0 

0 

553 

152.200 

Sept. 

.36.100 

820,100 

236,000 

2,300 

236,000 

0 

0 

0 

507 

1,33,200 

Oct. 

25,400 

617,900 

93,000 

1,,500 

93,000 

0 

0 

0 

477 

48,000 

Nov. 

21,900 

548,800 

0 

900 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

19,600 

569,800 

0 

0 

0 

0 

0 

0 

0 

1,860,100 

1,800,000 

18,600 

1,805,100 

57,600 

69,200 

0 

532 

87,500 

1918 

Jan. 

20.500 

589,400 

0 

0 

0 

0 

0 

0 

0 

Feb. 

36.800 

609,900 

47,000 

0 

47,000 

0 

0 

0 

484 

27.200 

Mar. 

140,000 

599,700 

119,000 

0 

119,000 

0 

0 

0 

483 

62,200 

April 
May 

179,000 

829,700 

261,000 

1,400 

261.000 

0 

0 

0 

477 

139,300 

307,000 

546,300 

261,000 

1,800 

261,000 

0 

0 

0 

470 

132,900 

June 

494,000 

590,500 

261,000 

2,200 

261,000 

0 

0 

0 

510 

147,800 

July 

121.000 

821,300 

261,000 

3,400 

261,000 

0 

0 

0 

517 

144,600 

Aug. 

42,800 

677,900 

261.000 

2.700 

261.000 

0 

0 

0 

467 

132,100 

Sept. 

48,700 

457,000 

236,000 

1,600 

236,000 

0 

0 

0 

403 

106,100 

Oct. 

103,000 

298,100 

93,000 

900 

93,000 

0 

0 

0 

382 

38,300 

Nov. 

44,000 

277,200 

0 

600 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

50,700 

320,600 

0 

0 

0 

0 

0 

0 

0 

1,596,500 

1,800,000 

14,600 

1,800,000 

0 

0 

0 

466 

77.700 

1919 

Jan. 

38,400 

371,300 

0 

0 

0 

0 

0 

0 

0 

Feb. 

08,900 

409,700 

47,000 

0 

47,000 

0 

0 

0 

430 

24,300 

Mar. 

94,100 

431,600 

119,000 

0 

119,000 

0 

0 

0 

427 

55,000 

April 
May 

209,000 

406,700 

261.000 

1,100 

261,000 

0 

0 

0 

407 

118.600 

441,000 

3.W,600 

261,000 

1.300 

261,000 

0 

0 

0 

430 

121.500 

June 

154,000 

532,300 

261,000 

2,100 

261,000 

0 

0 

0 

447 

130,600 

July 

61,500 

423.200 

261,000 

2,100 

261,000 

0 

0 

0 

389 

109,500 

Aug. 

30,400 

221,600 

250,300 

1,700 

92,600 

0 

0 

10,700 

320 

30,800 

Sept. 

23,000 

0 

23,000 

0 

0 

0 

0 

213,000 

0 

Got. 

22,400 

0 

22,400 

0 

0 

0 

0 

70,600 

0 

Nov. 

18,600 

0 

0 

0 

0 

0 

0 

0 

0 

Deo. 
Total  or 

30,100 

18,600 

0 

0 

0 

0 

0 

0 

0 

average 

1,191,400 

1,505.700 

8,300 

1,302,600 

0 

0 

294,300 

416 

49,200 

THE    CONTROL   OP    FLOODS   BY    RESERVOIRS.  347 

RESERVOIR  ON  SAN  JOAQUIN  RIVER. 

FOR  TWO  METHODS  OF  FLOOD  CONTROL. 
Carried  out  on  a  Daily  Basis. 

mary,  see  Table  10,  page  13fci.) 

supply  in  years  of  deficiency.     No  deduction  for  downstream  prior  rights.) 

Installed  capacity  of  power  plant  220,000  k.v.a.     P. F.  =0.80. 


Flood  con 

rol,  holding 

maximum  space  required  (rain-water  floods,  133,000  ac.-ft.; 

snow-water  floods,  177,000  ac.-ft.)  In  reserve  throughout  flood  season 

Maximum  controlled  flow  at  Friant— rain-water  floods,  10 

700  seo.-ft  ; 

3now-witer  floods,  14,200  sec.-ft. 

Irrigation 

Stage  of 
reservoir 

draft 

in 

acre-feet 

Evapora- 
tion in 
acre-ieet 

Power 
draft 

Release 
through 

Waste 

Defieieney 
in 

Average 
power 
head 

Average 
power 

yield  in 

kilowatts 
(Load 

factnr= 
1.00) 

Year  and 
month 

at 

beginning 

of 
month  in 
acre-feet 

(no 
deduction 
for  down- 
stream 
prior 

through 
turbines 

in 
acre-feet 

flood 

control 

outlets  in 

acre-feet 

over 
spillway 

in 
acre-feet 

irrigation 
supply 

in 
aere-teet 

through 

period 

of 

operation 
in  feet 

rights) 

1916 

465.800 

0 

0 

0 

0 

0 

0 

0 

.Ian. 

638,800 

47,000 

0 

47,000 

0 

0 

0 

504 

27,300 

Feb 

733.800 

119,000 

0 

129,400 

4.400 

0 

0 

.536 

73,800 

Mar. 

9.38,000 

261.000 

1,800 

264,100 

108,700 

4,200 

0 

566 

161,900 

April 

1,036.200 

261,000 

2,600 

282,900 

408,700 

0 

0 

551 

164,400 

May 

894,000 

261,000 

2,900 

276,900 

292,200 

0 

0 

542 

164,400 

.lune 

894,000 

261.000 

3,400 

272,600 

38,100 

0 

0 

546 

157,400 

July 

868,900 

261,000 

3,100 

261,000 

0 

0 

0 

524 

146,100 

.\ug. 

695.800 

236,000 

2,100 

236,000 

0 

0 

0 

476 

125,800 

Sept. 

502,600 

93,000 

1.300 

93,000 

0 

0 

0 

451 

45,400 

Oct. 

472.200 

0 

800 

0 

0 

0 

0 

0 

Nov. 

510,300 

0 

0 

0 

0 

0 

0 

0 

Dee. 
Totiil  or 
average 

1,800,00 

18000 

1,862,900 

852,100 

4,200 

0 

522 

89,000 

1917 

555,600 

0 

0 

0 

0 

0 

0 

0 

Jan. 

603,100 

47,000 

0 

47,000 

0 

0 

0 

489 

27,500 

Feb. 

685,100 

119,000 

0 

119,000 

0 

0 

0 

502 

64,400 

Mar. 

674,100 

261,000 

1,500 

261,000 

0 

0 

0 

488 

142,400 

April 

637,600 

261,000 

2,000 

261,000 

0 

0 

0 

501 

140,900 

May 

747,600 

261,000 

2,600 

270,500 

159,500 

0 

0 

537 

159,400 

June 

894,000 

261,000 

3,400 

267,400 

10,000 

0 

0 

544 

154,000 

July 

835,200 

261,000 

.3,100 

201,000 

0 

0 

0 

.536 

148,900 

Aug. 

643,700 

236,000 

2,000 

236,000 

0 

0 

0 

461 

121,800 

Sept. 

441,800 

93,000 

1,200 

93,000 

0 

0 

0 

422 

42,500 

Oct. 

373,000 

0 

700 

0 

0 

0 

0 

0 

Nov. 

394,200 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,800,000 

16,.500 

1,815,900 

160,.500 

0 

0 

498 

83,700 

1918 

413,800 

0 

0 

0 

0 

0 

0 

0 

Jan. 

434,300 

47,000 

0 

47,000 

0 

0 

0 

4,32 

24,400 

Feb. 

424,100 

119,000 

0 

119,000 

0 

0 

0 

431 

55,.500 

Mar. 

4.54,100 

261,000 

1,200 

261,000 

0 

0 

0 

422 

122,900 

April 

370,900 

261.000 

1.400 

261,000 

0 

0 

0 

415 

117,100 

May 

415,500 

261,000 

1,800 

261,000 

0 

0 

0 

464 

1.35,600 

June 

646,700 

261.000 

2.800 

261,000 

0 

0 

0 

473 

133.600 

July 

503,900 

261.000 

2.200 

261,000 

0 

0 

0 

411 

116,000 

Aug. 

283,500 

236,000 

1,200 

17.3,100 

0 

0 

0 

334 

63,100 

Sept. 

95.000 

93,000 

400 

18,000 

0 

0 

0 

296 

5,400 

Get. 

104,600 

0 

300 

0 

0 

0 

0 

0 

Nov. 

148,300 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

1,800,000 

11,300 

1,662,100 

0 

0 

0 

423 

64,600 

1919 

199,000 

0 

0 

0 

0 

0 

0 

0 

Jan. 

237,400 

47,000 

0 

47,000 

0 

0 

0 

360 

20,100 

Feb. 

259,300 

119,000 

0 

119,000 

0 

0 

0 

357 

45,400 

Mar. 

234,400 

261,000 

800 

261,000 

0 

0 

0 

333 

94,600 

April 

181,600 

261,000 

900 

261,000 

0 

0 

0 

363 

101,600 

May 

360,700 

261,000 

1.600 

261,000 

0 

0 

0 

.386 

112,400 

June 

252,100 

261,000 

1.500 

151,500 

0 

0 

0 

328 

52,200 

July 

51,100 

81,400 

100 

0 

0 

0 

179,600 

0 

Aug 

0 

23,000 

0 

0 

0 

0 

213,000 

0 

Se  )t. 

0 

22,400 

0 

0 

0 

0 

70,600 

0 

Oct. 

0 

0 

0 

0 

0 

0 

0 

0 

Nov. 

18,600 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Totsl  or 
average 

1,336,800 

4,900 

1,100,.500 

0 

0 

463,200 

357 

35,,500 

348 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  10a  (Continued).     TEMPERANCE  FLAT 

COMPARISON  OF  WATER  AND  POWER  YIELD 

Monthly  Summary  of  Computations 

(For  corresponding  yearly  sum 

Seasonal  irrigation  yield  1,800,000  acre-feet.    (Supplemented  by  ground  water 

Height  of  dam  595  feet.     Capacity  of  reservoir  1,071,000  acre-feet. 


Flood  control  by  reservoir  operatino  diagram 

Maximum  coiitroll 

id  flow  at  I 

runt— rail 

-water  ttiiods.  10.700  sec.-ft.; 

snow-water 

fijods,  U, 

OJsec-ft. 

Maximum  reservoir  space  required — rair. 

-watei  fljcds,  133.000  ac.-it.; 

now-water  floods,  177 

000  ac-ft. 

Run-off 
at 

Irrigation 

Year  and 
iii(j".th 

Friant 
in 

acre-ieol 

Stage  of 
•eiervoir 

drift 

in 

acre-fee. 

Power 

dr.ft 

Rele  se 
through 

Waste 

De5cie;:cy 
in 

.Average 
power 
head 

.\vor:'ge 
power 

yield  in 

kibwatts 
(Load 

factor- 
1.00) 

at 
>eginning 

01 

month  in 
i(ire-feet 

(no 
deduction 
for  down- 
stream 
prior 

Evapora- 
tion in 
■icre-feet 

through 
tur'iines 

in 
acre-feet 

fljod 
control 
outlets  in 
acre-feet 

O'er 
spillway 

in 
acre-feet 

i  rigatiui 
supply 

in 
acre-feet 

through 

period 

oi 

oper  tion 

in  feet 

rights) 

1920 

Jan. 

20,900 

48,700 

0 

0 

0 

0 

0 

0 

0 

Feb. 

28.900 

75,600 

47,000 

0 

0 

0 

0 

0 

0 

Mar. 

101,000 

57,.500 

119,000 

0 

0 

0 

0 

0 

0 

April 

161,000 

39,500 

198.000 

0 

0 

0 

0 

63,000 

0 

May 

407,000 

2,500 

253,600 

0 

8,400 

0 

0 

1,400 

298 

2,600 

June 

327,000 

149,900 

261,000 

900 

261,000 

0 

0 

0 

336 

95,700 

July 

111,000 

215,000 

261,000 

1,400 

151,500 

0 

0 

0 

320 

50,500 

Aug. 

45,400 

63,600 

108,900 

100 

0 

0 

0 

152,100 

0 

Sept. 

29,200 

0 

29  200 

0 

0 

0 

0 

206,800 

0 

Oct. 

37,000 

0 

37,000 

0 

0 

0 

0 

56,000 

0 

Nov. 

44,600 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

43.000 

44,600 

0 

0 

0 

0 

0 

0 

0 

1,362,000 

1,320,700 

2,400 

420,900 

0 

0 

479,300 

329 

12,300 

1921 

Jan. 

67,600 

87,600 

0 

0 

0 

0 

0 

0 

0 

Feb. 

77,800 

155,200 

47,000 

0 

47,000 

0 

0 

0 

317 

17.100 

Mar. 

162,000 

186,000 

119,000 

0 

119,000 

0 

0 

0 

340 

42,900 

April 

18'.),000 

220,000 

261,000 

700 

261,000 

0 

0 

0 

322 

90,700 

May 

323,000 

156,300 

261.000 

800 

261.000 

0 

0 

0 

324 

88,400 

June 

407,000 

217.500 

201,000 

1.200 

261,000 

0 

0 

0 

379 

110,100 

July 

155,000 

362.300 

261,000 

!  ,400 

261,000 

0 

0 

0 

390 

109,900 

Aug. 

51,600 

254,900 

261,000 

1,400 

151,500 

0 

0 

0 

327 

52,000 

Sept. 

34,700 

44,100 

78,700 

100 

0 

0 

0 

1.57,300 

0 

Oct. 

26,300 

0 

26,300 

0 

0 

0 

0 

66,700 

0 

Nov. 

23,000 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

63,300 

23,000 

0 

0 

0 

0 

0 

0 

0 

1,. 580,300 

1,576,000 

5,600 

1,361,500 

0 

0 

224,000 

344 

42,700 

1922 

Jan. 

67,600 

86,300 

0 

0 

0 

0 

0 

0 

0 

Feb. 

96.100 

153,900 

47,000 

0 

47,000 

0 

0 

0 

32  i 

17.400 

Mar. 

103,000 

203,000 

119,000 

0 

119,000 

0 

0 

0 

328 

41,000 

April 
May 

19.?,000 

187,000 

261,000 

700 

130.500 

0 

0 

0 

308 

42.8(X) 

621,000 

118,300 

261,000 

700 

244,200 

0 

0 

0 

367 

96,200 

June 

732,000 

477,600 

261,000 

1,900 

201,000 

0 

0 

0 

512 

145,300 

July 

270,000 

946,700 

261.000 

3.000 

261,000 

0 

0 

0 

565 

154,600 

Aug. 

84,800 

9,52,100 

261,000 

3,000 

261,000 

0 

0 

0 

542 

150.000 

Sept. 

43,400 

772,300 

236,000 

2,200 

230,000 

0 

0 

0 

498 

131.000 

Oct. 

31,900 

577,500 

93,000 

1,400 

93,000 

0 

0 

0 

466 

46,900 

Nov. 

42.400 

515,000 

0 

900 

0 

0 

0 

0 

0 

Dec. 

91,600 

556,500 

0 

0 

0 

0 

0 

0 

0 

Total  or 

average 

2,370,800 

1,800.000 

15,000 

1,652,700 

c 

0 

0 

443 

69.310 

1923 

Jan. 

69,.5O0 

648,100 

0 

0 

0 

0 

0 

0 

0 

Feb. 

70,000 

717,600 

47,000 

0 

47,000 

0 

0 

0 

520 

29.000 

Mar. 

95,900 

740,600 

1 19,000 

0 

119,000 

0 

0 

0 

513 

65,000 

April 
May 

199,000 

717,.5O0 

201,000 

1,600 

261,000 

0 

0 

0 

,500 

14,5,400 

450,000 

653,900 

261.000 

2,000 

261.000 
261,000 

0 

0 

0 

513 

143.800 

June 

287,000 

840,900 

261,000 

2.800 

0 

0 

0 

538 

1,54.200 

July 

201,000 

864,100 

261,000 

3,300 

261.000 

0 

0 

0 

539 

149,500 

Aug. 

72.600 

800,800 

261,000 

2,900 

261,000 

0 

0 

0 

507 

142,300 

Sept. 

50.900 

609,500 

230,000 

1,900 

236,000 

0 

0 

0 

453 

110,900 

Oct. 

48,300 

422,.5O0 

93,000 

1,200 

93.000 

0 

0 

0 

420 

42,200 

Nov. 

33,000 

376,600 

0 

700 

0 

0 

0 

0 

0 

Dec. 

Total  or 

27,700 

408,900 

0 

0 

0 

0 

0 

0 

0 

average 

1,604,900 

1.800,000 

16,400 

1,800,000 

0 

0 

0 

500 

82,900 

THE    CONTROL   OF    FLOODS   BY    RESERVOIRS.  349 

RESERVOIR  ON  SAN  JOAQUIN  RIVER. 

FOR  TWO  METHODS  OF  FLOOD  CONTROL. 

Carried  out  on  a  Daily  Basis. 

mary,  see  Table  10,  page  13b.) 

supply  in  years  of  deficiency.     No  deduction  for  downstream  prior  rights.) 

Installed  capacity  of  power  plant  220,000  k.v.a.     P. F.  =  0.80. 


Flood  control,  holding  maximum  space  required  (rair-water  floods,  133,000  ac.-ft.; 

snow-water  floods,  177,000  ac.-ff.)  in  reserve  through 

out  flood  season 

Maximum  controlled  flow  at  Friant— raiii-wa 

erfl3ods.  10,700  sec.-ft.; 

snow-water 

fliods,  14,200  sec.-ft. 

Irrigation 

Stage  of 

draft 
in 

Power 

Release 

Waste 

over 

spillw.-iy 

in 
acre-feet 

Deficiency 

Average 
power 

Average 

Year  and 

reservoir 

at 
leginniiig 

of 
month  in 
acre-feet 

acre-feet 

(no 
deduction 
for  down- 
stream 
prior 

Evapora- 
tion in 
acre-feet 

draft 
through 
turbines 

in 
acre-feet 

through 

flood 

control 

outlets  in 

acre-feet 

in 

irrigation 

supply 

in 
acre-feet 

head 

through 

period 

of 

operation 

in  feet 

power 
yield  in 
kilowatts 

(Load 
factor= 

1.00) 

month 

rights) 

1920 

48,700 

0 

0 

0 

0 

0 

0 

0 

Jan 

75,600 

47,000 

0 

0 

0 

0 

0 

0 

Feb. 

57,500 

119,000 

0 

0 

0 

0 

0 

0 

Mar. 

39,500 

198,000 

0 

0 

0 

0 

63,000 

0 

April 

2,500 

259,600 

0 

8,400 

0 

0 

1,400 

298 

2,600 

May 

119,900 

261,000 

900 

261,000 

0 

0 

0 

336 

95,700 

June 

215.000 

261,000 

1,400 

151,500 

0 

0 

0 

320 

50,500 

July 

63,600 

108,900 

100 

0 

0 

0 

152,100 

0 

Aug. 

0 

29,200 

0 

0 

0 

0 

206,800 

0 

Sept. 

0 

37,000 

0 

0 

0 

0 

56,000 

0 

Oct. 

0 

0 

0 

0 

0 

0 

0 

0 

Nov. 

44,600 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  r.T 
average 

1,320,700 

2,400 

420,900 

0 

0 

479,300 

329 

12,300 

1921 

87,600 

0 

0 

0 

0 

0 

0 

0 

Jan. 

155.200 

47,000 

0 

47,000 

0 

0 

0 

3i7 

17,100 

Feb. 

186,000 

119,000 

0 

119,000 

0 

0 

0 

340 

42,900 

Mar. 

229,000 

261.000 

700 

261,000 

0 

0 

0 

322 

90,700 

April 

156,300 

261,000 

800 

261,000 

0 

0 

0 

324 

88,400 

May 

217,500 

261,000 

1,200 

261,000 

0 

0 

0 

379 

110,100 

June 

362,300 

261.000 

1,400 

261,000 

0 

0 

0 

390 

109,900 

Julv 

254, f  00 

261,000 

1,400 

151,500 

0 

0 

0 

327 

52,000 

Aug. 

44,100 

78,700 

100 

0 

0 

0 

157,300 

0 

Sept. 

0 

26,300 

0 

0 

0 

0 

66,700 

0 

Oct. 

0 

0 

0 

0 

n 

0 

0 

0 

Nov. 

23,000 

0 

0 

0 

0 

0 

0 

0 

Dee. 
Total  or 

1,576.600 

5,600 

1,361,500 

0 

0 

224,000 

344 

42,700 

average 
1922 

86,300 

0 

0 

0 

0 

0 

0 

0 

Jan. 

153,900 

47,000 

0 

47,000 

0 

0 

0 

321 

17,400 

Feb. 

203,000 

119,000 

0 

119,000 

0 

0 

0 

328 

41,000 

Mar, 

187,000 

261,000 

700 

130,500 

0 

0 

0 

308 

42.800 

April 

118.300 

261.000 

700 

244,200 

0 

0 

0 

367 

96,200 

Mav 

477,600 

261.000 

1,900 

263,600 

50,100 

0 

0 

510 

148.900 

June 

894,000 

261.000 

3.400 

270,600 

41,300 

0 

0 

544 

156,100 

Jiilv 

848,700 

261,000 

3,100 

261,000 

0 

0 

0 

518 

144,900 

Aug 

669,400 

238,000 

2.000 

230,000 

0 

0 

0 

470 

124.300 

Sept . 

474,800 

93,000 

1,200 

93,000 

0 

0 

0 

4.35 

43,800 

Oct. 

412,500 

0 

800 

0 

0 

0 

0 

0 

Nov. 

4.54,100 

0 

0 

0 

0 

0 

0 

0 

Dee. 
Total  or 
average 

1,800,000 

13,800 

1,664,900 

91,400 

0 

0 

431 

68,200 

1923 

545,700 

0 

0 

0 

0 

0 

0 

0 

Jan. 

615,200 

47,000 

0 

47,000 

0 

0 

0 

494 

27,800 

Feb. 

638,200 

119,000 

0 

119,000 

0 

0 

0 

489 

62,900 

Mar 

61.5,100 

261,000 

1,400 

261,000 

0 

0 

0 

474 

1.38,.500 

April 

551,700 

261,000 

1,800 

261,000 

488 

137,800 

May 

738,900 

261,000 

2,600 

261,000 

516 

149,300 

June 

702,.30O 

261,000 

3,100 

261.000 

520 

145.300 

July 

099,200 

261,000 

2,700 

261,000 

480 

135,.500 

Aug, 

508,100 

236,000 

1,700 

236,000 

420 

1 10.800 

Sept. 

321,.30O 

93,000 

1,000 

93,000 

0 

.381 

38,200 

Oct, 

275.600 

0 

600 

0 

0 

0 

Nov, 

308,000 

0 

0 

0 

0 

0 

0 

0 

Dee. 
Total  or 

1,800,000 

14,900 

1,800,000 

0 

0 

0 

473 

79,000 

average 

;joO 


WATER   KESOUKCES   OF    CALIFORNIA. 


TABLE  10a  (Concludedj.     TEMPERANCE  FLAT 

COMPARISON  OF  WATER  AND  POWER  YIELD 

Monthly  Summary  of  Computations 
(For  corresponding  yearly  sum 
Seasonal  irrigation  yield  1,800,000  acre-feet.    (Supplemented  by  ground  water 
Height  of  dam  595  feet.     Capacity  of  reservoir  1,071,000  acre-feet. 


Flood 

control  by  reservoir  operating  diagram 

Maximum  control 

';d  flaw  at  Ftiiiit— rai 

■--water  floo 

ds,  10,700  sec.-ft.; 

snow-water  floods,  14. 

200scc.-ft. 

Maximum  reservoir  space  required — rair 

-wUerflvids,  133,033 

ac.-ft.; 

snow-water  floods,  177,000  ac.-ft. 

Run-off 

at 

Irrigation 

Year  and 

Friant 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

draft 

Average 

Average 
power 

yield  in 

kilowatts 
(Load 

factor=^ 
1.00) 

month 

in 
acre-fee t 

in 
acre-feet 

(no 
deduction 
for  down- 
stream 
prior 

Evapora- 
tion in 
acrc-fect 

Power 

draft 

through 

turbines 

in 
acre-feet 

Release 
through 
flood 
control 
outlets  in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Deficiency 

in 

irrigation 

supply 

in 
acre-feet 

power 

head 

through 

period 

of 

operation 

in  feet 

rights) 

1924 

.Tan. 

26,900 

436,000 

0 

0 

0 

0 

0 

0 

0 

Fob. 

22.600 

463,500 

47,000 

0 

47.000 

0 

0 

0 

445 

24.100 

Mar. 

25,800 

439,100 

119,000 

0 

119,000 

0 

0 

0 

419 

54,000 

April 

83,300 

345,000 

261,000 

1,000 

261,000 

0 

0 

0 

356 

102.600 

May 

1.52,000 

167,200 

261,000 

800 

109,400 

0 

0 

0 

304 

34,100 

June 

37.800 

57,400 

95,100 

100 

0 

0 

0 

165,900 

0 

July 

20,600 

0 

20,600 

0 

0 

0 

0 

240,400 

0 

Aug. 

16,200 

0 

16,200 

0 

0 

0 

0 

244,800 

0 

Sept. 

12,700 

0 

12,700 

0 

0 

0 

0 

223,300 

0 

Oct. 

11,700 

0 

11,700 

0 

0 

0 

0 

81,300 

0 

Nov. 

27.800 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total'Or 
average 

28,700 

27,800 

0 

0 

0 

0 

0 

0 

0 

466,100 

844,300 

1,900 

.536,400 

0 

0 

955,700 

391 

17,800 

1925 

Jan. 

27,100 

56,500 

0 

0 

0 

0 

0 

0 

0 

Feb. 

77,800 

83,600 

47,000 

0 

0 

0 

0 

0 

0 

Mar. 

04,700 

114,400 

119,000 

0 

0 

0 

0 

0 

0 

April 

106,000 

90,100 

261,000 

400 

0 

0 

0 

0 

0 

May 

364,000 

24,700 

261,000 

200 

0 

0 

0 

0 

0 

June 

281,000 

127,500 

261,000 

800 

60,900 

0 

0 

0 

298 

19.000 

Jub' 

1.51,000 

146,700 

261,000 

1,100 

5O,.5O0 

0 

0 

0 

298 

15,300 

AUR. 

65,800 

35,600 

101,.300 

100 

0 

0 

0 

159,700 

0 

Sept. 

.37,100 

0 

37,100 

0 

0 

0 

0 

198,900 

... 

0 

Oct. 

39,200 

0 

30,200 

0 

0 

0 

0 

53,800 

0 

Nov. 

38,900 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

40,800 

38,900 

0 

0 

0 

0 

0 

0 

0 

1,41.3.400 

1,387,600 

2,600 

111,400 

0 

0 

412,400 

298 

2.900 

Total  for 

18-year 

ppriod. 

1908-1926 

32,675,600 

28,984,500 

219,800 

25.010,400 

3,530,700 

442,500 

3,415,500 

Average 
for 

18-year 

period. 

1908-1926 

1.815,300 

1,610,300 

12,200 

1,389,500 

196.100 

24.600 

189,700 

484 

61,400 

THE    CONTROL    OF    FLOODS   BY    RESERVOIRS.  351 

RESERVOIR  ON  SAN  JOAQUIN  RIVER. 

FOR  TWO  METHODS  OF  FLOOD  CONTROL. 
Carried  out  on  a  Daily  Basis. 

mary,  see  Table  10,  page  13b.) 

supply  in  years  of  deficiency.     No  deduction  for  downstream  prior  rights.) 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.F.  =  0.80. 


Flood  con 

trol,  holding 

maximum  space  required  (rain-water  floods,  133,000  ac.-ft.; 

snow-water  floods,  177,000  ac.-ft.)  in  reserve  throughout  flood  season 

Maximum  controlied  flow  at  Fria 

nt — rain-water  floods,  10,700  aec.-ft.;  snow-water  floods,  14,200  sec.-ft. 

Irrigation 

Stage  of 
reservoir 

draft 

Average 

Average 
power 

Year  and 

in 
acre-feet 

Power 

draft 

Releiise 
through 

Waste 

Deficiency 
in 

power 
head 

month 

at 
beginning 

of 
month  in 
acre-feet 

(no 
deduction 
for  down- 
stream 
prior 
rights) 

Evapora- 
tion in 
acre-tect 

through 
turbines 

in 
acre-feet 

flood 

control 

outlets  in 

acre-feet 

over 
spillway 

in 
acre-teet 

irrigation 
supply 

in 
acre-feet 

through 

period 

of 

operation 

in  feet 

yield  in 
kilowatts 

(Load 
factor---- 

1.09) 

1924 

335,700 

0 

0 

0 

0 

0 

0 

0 

.Jan. 

302,600 

47,000 

0 

47,000 

0 

0 

0 

409 

22,300 

Feb. 

338,200 

119,000 

0 

1 19,000 

0 

0 

0 

380 

48,700 

Mar. 

245,000 

261,000 

800 

147,900 

0 

0 

0 

323 

51,500 

April 

66,500 

218,200 

300 

0 

0 

0 

42,800 

0 

May 

0 

37,800 

0 

0 

0 

0 

22.3,200 

0 

.June 

0 

20,600 

0 

0 

0 

0 

240.400 

0 

.Julv 

0 

16,200 

0 

0 

0 

0 

244,800 

0 

Aug. 

0 

12,700 

0 

0 

0 

0 

223,300 

0 

Sept. 

0 

11,700 

0 

0 

0 

0 

81,300 

0 

Oct. 

0 

0 

0 

0 

0 

0 

0 

0 

Nov. 

27,800 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

744,200 

1,100 

313,900 

0 

0 

1,055,800 

378 

10,100 

1925 

56,500 

0 

0 

0 

0 

0 

0 

0 

.Ian. 

83,600 

47,000 

0 

0 

0 

0 

0 

0 

Feb. 

114,400 

119,000 

0 

0 

0 

0 

0 

0 

M..r. 

90,100 

261,000 

400 

0 

0 

0 

0 

0 

April 

24,700 

261,000 

200 

0 

0 

0 

0 

0 

May 

127,500 

261,000 

800 

60,900 

0 

0 

0 

298 

19,000 

.lune 

146,700 

261,000 

1,100 

50,500 

0 

0 

0 

298 

15,300 

.lulv 

35,600 

101,300 

100 

0 

0 

0 

159,700 

0 

Aug. 

0 

37,100 

0 

0 

0 

0 

198,900 

0 

Sept. 

0 

39,200 

0 

0 

0 

0 

53,800 

0 

Oct. 

0 

0 

0 

0 

0 

0 

0 

0 

Nov 

38,900 

0 

0 

0 

0 

0 

0 

0 

Dee. 
Total  or 
average 

1,387,600 

2,600 

111,400 

0 

0 

412,400 

298 

2,900 

Total  for 

18-year 

28,705,100 

200,900 

24,491,100 

4,208,400 

4,200 

3,694,900 

period. 
1908-1926 

Average 

for 

18-yoar 

period, 
1908-1926 

1,594.700 

11,200 

1,360,600 

233,800 

200 

205,300 

467 

58,300 

352 


WATER   RESOURCES  OF    fALll'OKMA. 


TABLE  Ua.      TEMPERANCE   FLAT  RESERVOIR  ON  SAN  JOAQUIN  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  MONTHS 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  9a  and  10a. 

(For  corresponding  yearly  summary,  see  Table  11,  page  138.) 

Height  of  dam  595  feet.  Capacity  of  reservoir  1.071.000  acre-feet. 

Seasonal  irrigation  yield,  1,800,000  acre-feet.     (Supplemented  by  ground  water 

supply  in  years  of  deficiency.    No  deduction  for  downstream  prior  rights). 

Installed  capacity  of  power  plant  220,000  k.v.a.     P. F.  =0.80. 


Coordinated  with  flood  control  by 
ressrvoir  operating  diagram 

Maximum  controlled  flow  at 

Friiut — rain-water  floods. 

10.700  sec.-ft.;  snow-water 

floods,  14.200  sec.-ft. 

Flood  control,  holding  maximum 

reservoir  space  required  i  rain-water 

floods.  133.000  ac.-ft.;  snow-water 

floods.  177.000  ac.-ft.)  in  reserve 

Without  flood  control 

throughout  f^ood  season 

Maximum  reservoir  space 

required — rain-water  floods, 

133,000  ac.-ft.:  snow-water 

floods,  177,000  ac.-ft. 

Maximum  cnntr.-illed  flow  at 

Friant — rain-water  floods. 

10.700  sec.-ft.:  snow-water 

floods.  14.200  sec.-ft. 

Yfear  and 

month 

Irrigation 

Irrigation 

Irrigation 

draft  in 
acre-feet 

Deficiency 

.Average 
power 

draft  in 
acre-feet 

Deficiency 

.Average 
power 

draft  in 
acre-feet 

Deficiency 

.\veragc 
power 

fno 
deduction 

in 

irrigition 

supply 

jield  in 
kilowatts 

(no 
deduction 

in 

irrigation 

supply 

yield  in 
kilowatts 

(no 
deduction 

in 

irrigation 

supply 

yield  in 
kilowatts 

for  down- 

(Load 

for  down- 

(Load 

for  down- 

(Load 

stream 
prior 

in 
acre-feet 

factor= 
1.00) 

stream 
prior 

in 
acre-feet 

factor= 
1.00) 

stream 
prior 

in 
acre-feet 

factor= 
1.00) 

rights) 

rights) 

rights) 

1908 

Jan. 

0 

0 

0 

0 

0                   0 

0 

0 

0 

Feb. 

47.000 

0 

29.200 

47,000 

0 

29,200 

47.000 

0 

29.200 

Mar 

119,000 

0 

68.400 

119.000 

0 

68,400 

119.000 

0 

68.400 

April 

261.000 

0 

152.400 

261.000 

0 

152,400 

261.000 

0 

152,400 

May 

261.000 

0 

145,800 

261,000 

0 

145.800 

261,000 

0 

145.800 

Jane 

261.000 

0 

146.900 

261,000 

0 

146.900 

261.000 

0 

146.900 

July 

261.000 

0 

135.100 

261,000 

0 

135.100 

261.000 

0 

135.100 

Aug. 

261,000 

0 

121.100 

261.000 

0 

121,100 

261.000 

0 

121.100 

Sspt. 

236,000 

0 

86,800 

236.000 

0 

86,800 

236.000 

0 

86.800 

Oct. 

93,000 

0 

0 

93,000 

0 

0 

93.000 

0 

0 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Total  or 

average 

1.800,000 

0 

73,800 

1.800.000 

0 

73.800 

1.800.000 

0 

73.800 

1909 

Jan. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb 

17.000 

0 

24.700 

47.000 

0 

24.700 

47.000 

0 

24.700 

Mar. 

119.000 

0 

.59,300 

119.000 

0 

59.300 

119.000 

0 

59..300 

April 

261,000 

0 

1.34.200 

261.000 

0 

134.200 

261,000 

0 

1.34.200 

May 

261.000 

0 

147,700 

261.000 

0 

150.300 

261,000 

0 

151. .500 

June 

261,000 

0 

164.200 

261,000 

0 

164.400 

261.000 

0 

164.400 

July 

261.000 

0 

161.000 

261.000 

0 

156.600 

261.000 

0 

156.900 

Aug. 

261.000 

0 

152.400 

261,000 

0 

150.300 

261.000 

0 

144.400 

•Sept. 

236.000 

0 

1.34.200 

236,000 

0 

131.400 

236.000 

0 

123.300 

Oct. 

93.000 

0 

48.500 

93,000 

0 

47.200 

93.000 

0 

43,300 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

.0 

IVc. 
Total  or 

0 

0 

0 

0 

0 

0 

0 

0 

0 

ovrragc 

1.800.000 

0 

85.800 

i. 800,000 

0 

85.100 

1.800.000 

0 

83,700 

1910 

Jan. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47.000 

0 

31.500 

47,000 

0 

57.600 

47.000 

0 

30.400 

Mar. 

iin.ooo 

0 

109.7(K) 

119.000 

0 

73.800 

119.000 

0 

81.200 

April 
May 

261.000 

0 

163..5f)0 

261.000 

0 

162.600 

261.000 

0 

1.59,000 

261.000 

0 

164.400 

261. COO 

0 

164.400 

261.000 

0 

164,400 

June 

261,000 

0 

162.600 

261.000 

0 

157.400 

261,000 

0 

156.700 

July 

261.000 

0 

1J2.300 

261.000 

0 

145.200 

261.000 

0 

144,000 

Aug. 

261.000 

0 

142.900 

261.000 

0 

132.700 

261.000 

0 

131.000 

.Sept. 

236.000 

0 

120.400 

236.000 

0 

104.900 

236.000 

0 

104.200 

Oct. 

93,000 

0 

42,200 

93.000 

0 

35.500 

93.000 

0 

34,000 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

I>ec. 
'I'otal  or 

0 

0 
0 

0 

0 

0 

0 

0 

0 

0 

avi-r.ige 

1.800.000 

91.100 

1.800.000 

0 

86.200 

1,800.000 

0 

83.9C0 

THE    CONTROL    OF    FLOODS   BY    RESERVOIHS. 


353 


TABLE  11a  (Continued).     TEMPERANCE  FLAT  RESERVOIR  ON 
SAN  JOAQUIN  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  MONTHS 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  9a  and  10a. 

(For  corresponding  yearly  summary,  see  Table  11,  page  138.) 

Height  of  dam  595  feet.  Capacity  of  reservoir  1,071,000  acre-feet. 

Seasonal  irrigation  yield,  1,800,000  acre-feet.     (Supplemented  by  ground  water 

supply  in  years  of  deficiency.    No  deduction  for  downstream  prior  rights). 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.F.  =  0.80. 


Coordinated  with  flood  control  by 
reservoir  operating  dligram 

Maximum  3  )ntrolled  flow  at 

Friant — rain-water  floods, 

10,700  sec.-ft.;  snow-water 

floods,  14,200  sec.-ft. 

Flood  control,  holding  maximum 

reservoir  space  required  (rain-water 

floods,  133,000  ac.-ft.;  snow-water 

floods,  177,000  ac.-ft.)  in  reserve 

Without  flood  control 

throughout  flood  season 

Maximum  r  jservoir  space 

re'i  aired— rain-water  floods. 

133,030  ac.-ft.;  snow-water 

flaods,  177,000  ac.-ft. 

Maximum  c  )ntrolIed  flow  at 

Friant-rain-water  floods, 

10,700  sec.-ft.;  snow-water 

Hoods,  14,200  sec.-ft. 

Year  and 

month 

Irrigation 

Irrigation 

Irrigation 

draft  in 
acre-feet 

Deficiency 

Average 
power 

draft  in 
acre-feet 

Deficiency 

Average 
power 

draft  in 
acre-feet 

Deficiency 

Average 
power 

(no 
deduction 

irrigation 
supply 

yield  in 
kilowatts 

(no 
deduction 

in 

irrigitiou 

supply 

yield  in 
kilowatts 

(no 
deduction 

in 

irrigation 

supply 

yield  in 
kilowatts 

for  down- 

(Load 

for  down- 

(Load 

for  down- 

(Load 

stream 
prior 

in 
acre-feet 

factor= 
1.00) 

stream 
prior 

in 
acre-feet 

factor= 
1.00) 

stream 
prior 

in 
acre-feet 

factor= 
1.00) 

rights) 

rights) 

rights) 

1911 

.Ian. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47,000 

0 

29,200 

47,000 

0 

27,500 

47,000 

0 

27,200 

Mar. 

119,000 

0 

69,900 

119,000 

0 

66,700 

119,000 

0 

66,300 

April 

261,000 

0 

164..300 

261,000 

0 

158,900 

261,000 

0 

1.58,500 

May 

261,000 

0 

164,400 

261,000 

0 

164,000 

261,000 

0 

164,400 

June 

261,000 

0 

164,400 

261,000 

0 

164,400 

261,000 

0 

164,400 

July 

261,000 

0 

163,400 

261,000 

0 

163,300 

261,000 

0 

160,400 

Aug. 

261,000 

0 

155,200 

261,000 

0 

155,200 

261,000 

0 

154,800 

Sept. 

236,000 

0 

138,200 

236,000 

0 

1.38,200 

236,000 

0 

137,500 

Oct. 

93,000 

0 

50,700 

93,000 

0 

50,700 

93,000 

0 

50,400 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1,800,000 

0 

91,900 

1,800,000 

0 

91,000 

1,800,000 

0 

90,600 

1912 

Jan. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47,000 

0 

28.000 

47.000 

0 

28,000 

47,000 

0 

27,900 

Mar. 

119,000 

0 

64,700 

119,000 

0 

64,700 

119,000 

0 

64,400 

April 

261,000 

0 

136,700 

261,000 

0 

136,700 

261,000 

0 

135,600 

May 

261,000 

0 

121.800 

261,000 

0 

121,800 

261,000 

0 

120,600 

June 

261,000 

0 

137,900 

261,000 

0 

137,900 

261,000 

0 

136.800 

July 

261,000 

0 

12.^800 

261,000 

0 

125.800 

261,000 

0 

124,700 

Aug. 

261,000 

0 

102,700 

261,000 

0 

102,700 

261,000 

0 

101,100 

Sept. 

198,100 

37,900 

12,800 

198,100 

37,900 

12,800 

187,700 

48,390 

7,500 

Oct. 

17,800 

75,200 

0 

17,800 

75,200 

0 

17,800 

75,200 

0 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Deo. 

Total  or 

0 

0 

0 

0 

0 

0 

0 

0 

0 

average 

1,686,900 

113,100 

60,900 

1,686,900 

113,100 

60,900 

l,676,.'i00 

123,500 

59,900 

1913 

Jan. 

0 

0 

0 

0 

0 

0 

I) 

0 

0 

Feb. 

47,000 

0 

(1 

47,000 

0 

0 

47,000 

0 

0 

Mar. 

79,300 

39,700 

0 

79.300 

3!l,700 

0 

79.300 

39,700 

0 

April 

9.5,800 

165,200 

0 

95.800         165,200 

0 

95,800 

165,200 

0 

May 

219,200 

41.800 

0 

219,200           41,800 

0 

219,200 

41,800 

0 

June 

197,700 

()3,30n 

0 

197.700           (i3.300 

0 

197,700 

63,300 

0 

July 

102,000 

I. =19,000 

0 

102,000         159,001) 

0 

102.000 

15.),000 

0 

Aug. 

68.900 

192,100 

0 

68.900         192,100 

0 

68.900 

192,100 

0 

Sept. 

40,600 

195,400 

0 

40,600 

195,400 

0 

40.000 

195,400 

0 

Oct. 

12  800 

80,200 

0 

12,800 

80.2(M) 

0 

12,800 

80,200 

0 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Total  or 
average 

863,300 

863,300 

936,700 

0 

883,,300 

033,700 

0 

933,700 

0 

354 


WATER    RESOURCES   OF    CALIFORNIA. 


TABLE  Ua  (Continued).     TEMPERANCE  FLAT  RESERVOIR  ON 
SAN  JOAQUIN  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  MONTHS 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  9a  and  10a. 

(For  correspondng  yearly  summary,  see  Table  11,  page  138.) 

Height  of  dam  595  feet.  Capacity  of  reservoir  1,071,000  acre-feet. 

Seasonal  irrigation  yield,  1,800,000  acre-feet.    (Supplemented  by  ground  water 

supply  in  years  of  deficiency.    No  deduction  for  downstream  prior  rights). 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.F.  =  0.80. 


Coordinated  with  flood  control  by 

Flood  control,  holding 

Tiaximum 

reservoir  operating  diagram 

Maximum  controlled  flow  at 

reservoir  space  requiree  (rain-water 
floods,  133,000  ac.-ft.;  snow-water 

Friant — rain-water  floods. 

floods,  177,000  ac.-ft.) 

n  reserve 

Without  flood  control 

10,700  sec.-ft.;  snow 
floods,  14.200  sec 

-water 
-ft. 

throughout  flood  season 

Maximum  controlled  flow  at 

Maximum  reservoir  space 

required — rain-water  floods, 

133,000  ac.-ft.:  snow-water 

floods,  177,000  ac.-ft. 

Friant — rain-water 

10,700  sec.-ft.;  snow 

floods,  14,200  sec 

Joods. 
-water 
.-ft. 

Year  and 

month 

Irrigation 

Irrigation 

Irrigation 

draft  in 
acre-feet 

Deficiency 

Average 
power 

draft  in 
acre-feet 

Deficiency 

Average 
power 

draft  in 
acre-feet 

Deficiency 

Average 
power 

(no 
deduction 

in 

irrigation 
supply 

yield  in 
kilowatts 

(no 
deduction 

in 

irrigation 

supply 

yield  in 
kilowatts 

(no 
deduction 

in 

irrigation 

supply 

yield  in 
kilowatts 

for  down- 

(Load 

for  down- 

(Load 

for  down- 

(Load 

stream 
prior 

in 
acre-feet 

factor= 
1.00) 

stream 
prior 

in 
acre-feet 

factor= 
1.00) 

stream 
prior 

acre-feet 

factor= 
1.00) 

rights) 

rights) 

rights) 

1914 

Jan. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47,000 

0 

22,800 

47,000 

0 

22,800 

47,000 

0 

22,800 

Mar. 

119,000 

0 

56,600 

119,000 

0 

56,600 

119,000 

0 

56,600 

April 

261,000 

0 

138.800 

261,000 

0 

138.800 

261.000 

0 

138.800 

May 

261.000 

0 

145,300 

261,000 

0 

146,800 

261,000 

0 

147,200 

June 

261,000 

0 

163,800 

261,000 

0 

164.400 

261.000 

0 

164,400 

July 

261,000 

0 

162„500 

261,000 

0 

158,600 

261,000 

0 

157,900 

Aug. 

261,000 

0 

156,100 

261,000 

0 

156,100 

261,000 

0 

149,700 

Sept. 

236,000 

0 

139,300 

236,000 

0 

139,000 

236.000 

0 

131,900 

Oct. 

93,000 

0 

51,300 

93,000 

0 

51.200 

93,000 

0 

47,800 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1,800,000 

0 

86,600 

1,800,000 

0 

86,400 

1,800,000 

0 

85,000 

1915 

Jan. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47,000 

0 

29,800 

47,000 

0 

29,600 

47,000 

0 

28,100 

Mar. 

119,000 

0 

68,100 

119,000 

0 

67,900 

119,000 

0 

64.400 

April 

261,000 

0 

153,100 

261,000 

0 

152.800 

261, (X)0 

0 

144.600 

May 

261,000 

0 

149,900 

261,000 

0 

151,100 

261.000 

0 

142.100 

June 

261,000 

0 

163,300 

261,000 

0 

164,400 

261.000 

0 

161.900 

July 

261,000 

0 

160,800 

261,000 

0 

156,500 

261.000 

0 

156,900 

Aug. 

261,000 

0 

153,000 

261,000 

0 

150,700 

261,000 

0 

147,200 

Sept. 

236,000 

0 

134.600 

236,000 

0 

131,400 

236.000 

0 

123.800 

Oct. 

93.000 

0 

48,800 

93,000 

(1 

47,000 

93.000 

0 

43,,500 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 
Total  or 
average 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1,800,000 

0 

88,700 

1,800,000 

0 

87,800 

1,800,000 

0 

84,600 

1916 

Jan. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47.000 

0 

29,000 

47,000 

0 

28.400 

47,000 

0 

27,,300 

Mar. 

119.000 

0 

97,000 

119,000   1                 0 

72,000 

119.000 

0 

73,800 

April 

261,000 

0 

164.400 

261,000 

0 

164,400 

261,000 

0 

161.900 

May 

261,000 

n 

lfi4.4(M) 

261,000 

0 

164,400 

261.000 

0 

164,400 

June 

261.000 

0 

164.400 

261,(X)0 

0 

164,.300 

261,000 

0 

164,400 

July 

261.0<M) 

0 

161.300 

261,000 

0 

1.55,400 

261,000 

0 

157,400 

Aug. 

261,000 

0 

153.800 

261.000 

0 

151.700 

261, 0(X) 

0 

146.100 

Sept. 

236.000 

0 

135,800 

236.000 

0 

1,33,300 

236,000 

0 

125,800 

Oct. 

«3,00() 

0 

,50,100 

93,(MJ0 

0 

48,900 

93,000 

0 

45,400 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dee. 
Total  or 
average 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1,800,000 

0 

93.500 

1,800,000 

0 

90,300 

1,800,000 

0 

89.000 

THE    CONTROL    OF    FLOODS    BY    RESERVOIRS. 


355 


TABLE  11a  (Continued).     TEMPERANCE  FLAT  RESERVOIR  ON 
SAN  JOAQUIN  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  MONTHS 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  9a  and  10a. 

(For  corresponding  yearly  summary,  see  Table  11,  page  138.) 

Height  of  dam  595  feet.  Capacity  of  reservoir  1,071,000  acre-feet. 

Seasonal  irrigation  yield,  1,800,000  acre-feet.     (Supplemented  by  ground  water 

supply  in  years  of  deficiency.    No  deduction  for  downstream  prior  rights). 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.F.  =  0.80. 


Coordinated  with  flood  control  by 
reservoir  operating  diagram 

Maximum  controlled  flow  at 
Friant— rain-water  floods. 

Flood  control,  holding 

reservoir  space  required 

floods,  133,000  ac.-ft.: 

floods,  177,000  ac.-ft.) 

maximum 
(rain-water 
snow-water 
in  reserve 

Without  flood  control 

10,700         '■                  ' 
floo 

sec.-n.;  snow-waier 
is,  14,200  sec.-ft. 

throughout  flood  season 
Maximum  controlled  flow  at 

Maximum  reservoir  space 

Friant 

— rain-water  floods. 

required — rain-water  floods, 

133,000  ac.-ft.;  snow-water 

floods,  177,000  ac.-ft. 

10,700  sec.-ft.;  snow-water 
floods,  14,200  sec.-ft. 

Year  and 

month 

Irrigation 

Irrigation 

Irrigation 

draft  in 
acre-feet 

Deficiency 

Average 
power 

draft  in 
acre-feet 

Deficiency 

Average 
power 

draft  in 
acre-feet 

Deficiency 

Average 
power 

(no 
deduction 

irrigation 
supply 

yield  in 
kilowatts 

(no 
deduction 

irrigation 
supply 

yield  in 
kilowatts 

(no 
deduction 

irrigation 
supply 

yield  in 
kilowatts 

for  down- 

(Load 

for  down- 

(Load 

for  down- 

(Load 

stream 
prior 

in 
acre-feet 

factor= 
1.00) 

stream 
prior 

in 
acre-fee ! 

factor= 
1.00) 

stream 
prior 

in 
acre-fee! 

factor= 
1.00) 

rights) 

rights) 

rights) 

1917 

Jan. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47,000 

0 

29,500 

47,000 

0 

28.900 

47.000 

0 

27,500 

Mar. 

119,000 

0 

68,400 

119,000 

0 

67.300 

119,000 

0 

64,400 

April 

261.000 

0 

1.52,.500 

261.000 

0 

149.700 

261.000 

0 

142,400 

May 

261.000 

0 

149.600 

261,000 

0 

147.400 

261,000 

0 

140,900 

June 

261,000 

0 

162,600 

261,000 

0 

161,400 

261,000 

0 

159,400 

July 

261,000 

0 

159.100 

261,000 

0 

159.100 

261.000 

0 

1.54,000 

-^ug. 

261,000 

0 

1.52,200 

261,000 

0 

152.200 

261,000 

0 

148.900 

Sept. 

2,36.000 

0 

1.33,200 

236,000 

0 

13.3,200 

236,000 

0 

121,800 

Oct. 

93,000 

0 

48,000 

93,000 

0 

48,000 

93,000 

0 

42,500 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Total  or 
average 

1,800,000 

0 

88,100 

1,800,000 

0 

87,500 

1,800,000 

0 

83,700 

1918 

Jan. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47,000 

0 

27,200 

47,000 

0 

27,200 

47,000 

0 

24,400 

Mar. 

119,000 

0 

62,200 

119,000 

0 

62.200 

119,000 

0 

55.500 

April 

261,000 

0 

133,300 

261,000 

0 

139,300 

261.000 

0 

122,900 

May 

261,000 

0 

132,900 

261,000 

0 

132,900 

261.000 

0 

117,100 

June 

261,000 

0 

147,800 

261,000 

0 

147,800 

261.000 

0 

135,600 

July 

261,000 

0 

144,600 

261.000 

0 

144.600 

261.000 

0 

133,600 

Aug. 

261.000 

0 

132,100 

261,000 

0 

1.32,100 

261,000 

0 

116.000 

Sept. 

236,000 

0 

106,100 

236,000 

0 

106,100 

236,000 

0 

63,100 

Oct. 

93,000 

0 

38,300 

93,000 

0 

38,300 

93,000 

0 

5,400 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Total  or 
average 

1,800,000 

0 

77,700 

1,800,000 

0 

77,700 

1,800,000 

0 

64,600 

1919 

.Ian. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47,000 

0 

24,300 

47,000 

0 

24,300 

47,000 

0 

20,100 

Mar. 

119,000 

0 

55,000 

119,000 

0 

55,000 

119,000 

0 

45,400 

April 

261,000 

0 

118,600 

261,000 

0 

118,600 

261,000 

0 

94.600 

May 

261,000 

0 

121, .500 

261,000 

0 

121,500 

261,000 

0 

101,600 

June 

261,000 

0 

130,600 

261,000 

0 

130,600 

261,000 

0 

112,400 

July 

261,000 

0 

109..50O 

261,000 

0 

109,500 

261.000 

0 

52,200 

Aug. 

250,300 

10,700 

30,800 

2.50,300 

10,700 

30,800 

81.400 

179,600 

0 

Sept. 

23,000 

213,000 

0 

23,000 

213,000 

0 

23,000 

213,000 

0 

Oct. 

22,400 

70,600 

0 

22,400 

70,600 

0 

22,400 

70,600 

0 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1,505,700 

294.300 

49,200 

1,505,700 

294,300 

49,200 

1,336,800 

463,200 

35,500 

35fi  WATER    RESOURCES   OF    CALIFORNIA. 

TABLE  11a  (Continued).     TEMPERANCE  FLAT  RESERVOIR  ON 
SAN  JOAQUIN  RIVER. 

SUMMARY  OF  WATER  AND  POWER  YIELD  BY  MONTHS 

BOTH 

WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  9a  and  10a. 

(For  corresponding  yearly  summary,  see  Table  11,  page  138.") 

Height  of  dam  595  feet.  Capacity  of  reservoir  1,071,000  acre-feet. 

Seasonal  irrigation  yield,  1,800,000  acre-feet.     (Supplemented  by  ground  water 

supply  in  years  of  deficiency.    No  deduction  for  downstream  prior  rights). 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.F.  =0.80. 


Without  flood  control 

Coordinated  with  flood  control  by 

reservoir  operating  diagram 

Maximum  controlled  flow  at 

Friant — rain-water  floods. 

10.700  sec.-ft.:  snow-water 

floods,  14,200  sec.-ft. 

Flood  control,  holding  maximum 

reservoir  space  required  'rain-water 

floods,  133,000  ac.-ft.:  snow-water 

floods,  177,000  ac.-ft.)  in  reserve 

throughout  flood  season 

Maximum  controlled  flow  at 

Maximum  reservoir  space 
required — rain-water  floods. 

Friant 
10.700 

— rain-water  floods, 
sec.-ft.:  snow-water 

133.000  ac.-ft.;  snow-water 
floods,  177,000  ac.-ft. 

floods,  14.200  sec.-ft. 

Year  and 

month 

Irrigation 

Irrigation 

Irrigation 

draft  in 
acre-feet 

Deficiency 

.\verage 
power 

draft  in 
acre-feet 

Deficiency 

.Average 
power 

draft  in 
acre-feet 

Deficiency 

Average 
power 

Tno 
deduction 

irrigation 
supply 

yield  in 
kilowatts 

(no 
deduction 

in 

irrigation 

supply 

yield  in 
kilowatts 

(no 
deduction 

irrigation 
supply 

yield  in 
kilowatts 

for  down- 

(Load 

for  down- 

(Load 

for  down- 

(Load 

stream 
prior 

in 
acre-feet 

f3Ctor= 
1.00) 

stream 
prior 

in 
acre-feet 

factor^ 
1.00) 

stream 
prior 

ID 

acre-fee t 

factcr= 
1.00) 

rights) 

rights) 

rights) 

1920 

Jan. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47.000 

0 

0 

47,000 

0 

0 

47,000 

0 

0 

Mar. 

119,000 

0 

0 

119,000 

0 

0 

119,000 

0 

n 

April 

198,000 

63,000 

0 

198,000 

63,000 

0 

198,000 

63.000 

0 

May 

259,600 

1,400 

2,600 

259,600 

1,400 

2,600 

259,600 

1,400 

2,600 

June 

261,000 

0 

95.700 

261,000 

0 

95,700 

261,000 

0 

95.700 

July 

261.000 

0 

50,500 

261.000 

0 

50,500 

261,000 

0 

50.500 

Aug. 

108,900 

152,100 

0 

108,900 

152.100 

0 

108,900 

1S2.100 

0 

Sept. 

29.200 

206,800 

0 

29,200 

206,800 

0 

29,200 

206.800 

0 

Oct. 

37.000 

56,000 

0 

37.000 

56,000 

0 

37,000 

56.000 

0 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Der. 
Total  rr 
average 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1,320,700 

479,300 

12,300 

1.320,700 

479,300 

12,300 

1,320,700 

479,300 

12,300 

1921 

Jan. 

0 

0 

0 

0 

0 

0 

n 

0 

0 

Feb. 

47,000 

0 

17.100 

47.000 

0 

17.100 

47,000 

0 

17.100 

Mar. 

119.000 

0 

42,900 

119,000 

0 

42,900 

119.000 

0 

42.900 

April 

261,000 

0 

90.700 

261,000 

0 

90,700 

261,000 

0 

90.700 

May 

261.000 

0 

88,400 

261,000 

0 

88,400 

261,000 

0 

88.400 

June 

261,000 

0 

110,100 

261,000 

0 

110,100 

261,000 

0 

110.100 

July 

261,000 

0 

109.900 

261,000 

0 

109,900 

261,000 

0 

109,900 

Aug. 

261,000 

0 

52,000 

261,000 

0 

52,000 

261,000 

0 

52,000 

Sept. 

78,700 

157,300 

0 

78,700 

157,300 

0 

78,700 

157,300 

0 

Oct. 

26,300 

66,700 

0 

26,300 

66,700 

0 

26,300 

66,700 

0 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 

0 

0 

0 

0 

0 

0. 

0 

0 

0 

Total  or 
avrranc 

1.576,000 

224.000 

42.700 

l.J76,000 

224,000 

42.700 

1.576.000 

224,000 

42.700 

1922 

Jan. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47,000 

0 

17.400 

47,000 

0 

17,400 

47,000 

0 

17.400 

Mar. 

119,000 

0 

41.000 

119.000 

0 

41.000 

119,000 

0 

41.000 

April 

261,000 

0 

42.800 

261,000 

0 

42.800 

261,000 

0 

42,800 

May 

261.000 

0 

96.200 

261,000 

0 

96,200 

261,000 

0 

96,200 

June 

261,000 

0 

148,300 

261,000 

0 

148,300 

261.000 

0 

148,900 

July 

261,000 

0 

154,600 

261.000 

0 

154.600 

261,000 

0 

1,56.100 

Aug. 

261,000 

0 

150,000 

261,000 

0 

150,000 

261,000 

0 

144,900 

Sept. 

236,000 

0 

131,000 

236,000 

0 

131.000 

236.000 

0 

124.3C0 

Oct. 

93,000 

0 

46,900 

93,000 

0 

46.900 

93,000 

0 

43.800 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dee. 
Total  or 
average 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1.800.000 

0 

69.300 

1.800,000 

0 

69.300 

1,800,000 

0 

68.200 

THE    CONTROL   OK    FLOODS    BY    KESEHVOIRS. 


851 


TABLE  11a  (Concluded).     TEMPERANCE  FLAT  RESERVOIR  ON 
SAN  JOAQUIN  RIVER. 
SUMMARY  OF  WATER  AND  POWER  YIELD  BY  MONTHS 
BOTH   WITH  AND  WITHOUT  FLOOD  CONTROL. 

Summary  of  Tables  9a  and  10a. 

(For  corresponding  yearly  summary,  see  Table  1 1,  page  1  38.) 

Height  of  dam  595  feet.  Capacity  of  reservoir  1,071,000  acre-feet  • 

Seasonal  irrigation  yield,  1,800,000  acre-feet.     (Supplemented  by  ground  water 

supply  in  years  of  deficiency.    No  deduction  for  downstream  prior  rights). 

Installed  capacity  of  power  plant  220,000  k.v.a.     P.F.  =  0.80. 


Coordinated  with  flood  control  by 
reservoir  operating  diagram 

Ma.ximum  c mtrollcd  tlow  at 
Friant— rain-water  floods. 

Flood  control,  holding  maximum 

reservoir  space  required  (rain-water 

floods,  133,000  ac.-ft.;  snow-water 

floods,  177,000  ac.-ft.)  In  reserve 

Without  flood  control            | 

10,700  33C.-ft. :  snow 
fljods,  14,200  sec 

-waier 
-ft. 

throughout  flood  season 

Ma.\imum  controlled  flow  at 

Yei«r  ami 

Maximum  reservoir  space 

req  jired — rain-water  floods, 

133,000  ac.-ft.;  snow-water 

floods,  177,000  ac.-ft. 

Friant^rain-water  floods, 

10,700  sec.-ft.;  snow-water 

floods,  14,200  sec.-ft. 

month 

Irrigation 

Irrigation 

Irrigation 

draft  in 
acre-feet 

Deficiency 

Average 
power 

draft  in 
acre-feet 

Deficiency 
in 

Average 
power 

draft  in 
acre-feet 

Deficiency 
in 

Average 
power 

(no 
deduction 

irrigation 
supply 

vield  in 
kilowatts 

(no 
deduction 

irrigation 
supply 

yield  in 
kilowatts 

(no 
deduction 

irrigation 
supply 

yield  in 
kilowatts 

for  down- 

(Load 

for  down- 

(Load 

for  down- 

(Load 

stream 
prior 

in 
acre-feet 

factor= 
1.00) 

stream 
prior 

in 
acre-feet 

factor= 
1.00) 

stream 
prior 

in 
acre-feet 

factor = 
1.00) 

rights) 

rights) 

rights) 

1923 

Jan. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47,000 

0 

29,000 

47,000 

0 

29,000 

47,000 

0 

27,800 

Mar. 

110,000 

0 

65.600 

119,000 

0 

65,600 

119,000 

0 

62,900 

April 

261,000 

0 

145,400 

261,000 

0 

145.400 

261.000 

0 

138,.500 

May 

261.000 

0 

143,800 

261,000 

0 

143,800 

261,000 

0 

137,800 

June 

261,000 

0 

154,200 

261,000 

0 

154,200 

261,000 

0 

149,300 

July 

261,000 

0 

149,500 

261,000 

0 

149,500 

261,000 

0 

145,300 

Aug. 

261,000 

0 

142,300 

261,000 

0 

142,300 

261,000 

0 

135,.500 

Sept. 

2.36,000 

0 

119,900 

236.000 

0 

119,900 

236,000 

0 

110,800 

Oct. 

93,000 

0 

42,200 

93,000 

0 

42,200 

93.000 

0 

38.200 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 
average 

0 

0 

0 

0 

0 

0 

0 

0 

0 

1,800,000 

0 

82,900 

1,800,000 

0 

82,900 

1,800,000 

0 

79,000 

1924 

Jan. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47,000 

0 

24,100 

47,000 

0 

24.100 

47,000 

0 

22,300 

Mar. 

119.000 

0 

54,000 

119,000 

0 

54.000 

119,000 

0 

48,700 

April 

261,000 

0 

102,600 

261,000 

0 

102,600 

261,000 

0 

51, .500 

May 

261.000 

0 

34,100 

261.000 

0 

34,100 

218.200 

42,800 

0 

June 

95,100 

165.900 

0 

95,100 

165,900 

0 

37,800 

223,200 

0 

July 

20,600 

240.400 

0 

20,600 

240,400 

0 

20.600 

240,400 

0 

Aug. 

16.200 

244.800 

0 

16,200 

244,800 

0 

16,200 

244,800 

0 

Sept. 

12,700 

223.300 

0 

12,700 

223.300 

0 

12,700 

223,300 

0 

Oct. 

11,700 

81,300 

0 

11,700 

81,300 

0 

11,700 

81,300 

0 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 

Total  or 

0 

0 

0 

0 

0 

0 

0 

0 

0 

average 

844,.30O 

9.55,700 

17,800 

844,300 

955,700 

17,800 

744,200 

1,055.800 

10,100 

1925 

Jan. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Feb. 

47,000 

0 

0 

47,000 

0 

0 

47,000 

0 

0 

Mar. 

119,000 

0 

0 

1 19,000 

0 

0 

119,000 

0 

0 

April 

261,000 

0 

0 

261,000 

0 

0 

261,000 

0 

0 

May 

261,000 

0 

0 

261,000 

0 

0 

261,000 

0 

0 

June 

261.000 

0 

19,000 

261,000 

0 

19,000 

261,000 

0 

19,000 

July 

261,000 

0 

15,300 

261,000 

0 

15,300 

261,000 

0 

15,300 

Aug. 

101.300 

159,700 

0 

101,300 

159,700 

0 

101,300 

159,700 

0 

Sept. 

37,100 

198,900 

0 

37,100 

198.900 

0 

37,100 

198,900 

0 

Oct. 

39,200 

53,800 

0 

39,200 

53,800 

0 

39,200 

53,800 

0 

Nov. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Dec. 

0 

0 

0 

0 

0 

0 

0 

0 

0 

Total  or 

average 

1,387,600 

412,400 

2,900 

1,.387,600 

412,400 

2,900 

1,387,600 

412,400 

2,900 

Total  for 

18-year 

period, 

1908-1926 

28,984,500 

3,415,500 

28,984,500 

3,415,500 

28,705,100 

3,894.900 

Average 

for  18-yea 

period, 

1908-1926 

1,610,300 

189.700 

62,000 

1   1,610,300 

189,700 

1        61,400 

,   1,594,700 

1      205,300 

58,300 

358  WATER   RESOURCES   OF    CALIFORNIA. 

ASSUMPTIONS  EMPLOYED  IN  COMPUTING  WATER  YIELD  OF  SAN  GAB- 
RIEL   RESERVOIR   ON   SAN   GABRIEL    RIVER   ON    A    DAILY    BASIS 

1.  Wator  .sii])ply  at  dam  site  is  the  same  as  that  measured  at  the 
Aziisa  ofapfiiip:  station  of  tlie  United  States  (leoloofieal  Survey  and  pub- 
lished, or  in  preparation  for  ])ublication.  as  mean  daily  discharges  in 
the  Water  Supply  Pa])ers,  except  that  the  first  152  second-feet  of 
natural  flow  is  deducted  for  downstream  prior  rights. 

2.  The  reservoir  is  assumed  to  have  all  space  filled  below  the  117,350 
acre-feet  flood  control  reserve  of  January  1,  1897.  This  was  later  found 
to  be  an  improbable  condition  for  240,000  acre-feet  of  capacity 
employed  for  flood  control,  seasonal  and  over-year  storage  coordinated, 
but  quite  probable  for  180,000  acre-feet  of  capacity  or  less.  Tables 
13  and  13a  show  a  yield  of  41  second-feet  continuous  flow  on  this 
assumption  for  240,000  acre-feet  of  capacity,  but  the  period  ends  with 
61,300  acre-feet  less  water  in  storage  than  at  the  beginning.  The  exact 
yield  in  continuous  flow  for  the  ^leriod  analyzed  is  32  second-feet.  The 
exact  yield  in  flood  control  and  seasonally  stored  water  for  the  period 
is  22,300  and  25,900  acre-feet  per  season,  respectively.  It  is  given  as 
30,000  and  13,800  acre-feet  per  season,  respectively,  in  Tables  13  and  13a. 
The  yield  in  continuous  flow  of  240,000*  acre-feet  of  capacity  with  such 
water  in  storage  on  January  1,  1897,  as  probably  could  have  accumu- 
lated during  the  seasons  immediately  yireceding  1897,  is  closer  to  the  41 
second-feet  of  Tables  13  and  13a  than  to  32  second-feet,  the  exact  yield 
for  the  period  of  analysis.  The  exact  yields  of  the  period  of  analysis 
are  used  in  the  text  for  comparative  pur])os(»s  in  order  to  ]ilace  the 
information  compared  on  the  same  basis. 

3.  The  net  evaporation  from  the  reservoir  surface  equals  4.0  feet 
depth  ])er  annum,  divided  among  the  months  as  follows: 

Per  cent 

Depth  in  of  seasonal 

Month                                                                                          feet  total 

April    0.37  n.2 

May    0.50  12.6 

June    0.00  15.0 

July    0.71  17.8 

August 0.00  IG.G 

S«>ptoinber 0.51  12.7 

October  o.-'io  n.(; 

Xov.'inbcr    0.26  ti.". 


T..t:.ls    4.00  100.0 


r 


;{()()  WATEi;    KKSOl'IM'KS   OF    CALIFORXIA. 

TABLE  12a.     SAN  GABRIEL  RESER 

WATER  YIELD  UNDER 

FLOOD  CONTROL  AND  SEAS 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  cor 

trol  leserve  or  first 

180,000  acre- 

131,000  acre-feet  of  capacity 

Flood 

Flood 

control 

control 

Run-off 

at 
Azusa 

Passed 

water 

Passed 

water 

Year  and 
m,)ntii 

Stage  of 
reservoir 

by  dam 

for  prior 

rights 

pissing 
Azusa 
during 

Seasonally 

Evapora- 
tion 
from 

Waste 

Stage  of 
reservoir 

by  dam 

for  prior 

rights 

passing 
Azcsa 
daring 

in 

at 

(■first  152 

flood 

stored 

over 
spillway 

in 
acre-feet 

at 
beginning 

of 
month  in 
acre-feet 

ffirst  152 

flood 

acre-feet 

beginning 

of 
n.onth  in 
ae  re-feel 

second- 
fee  t  of 
ratural 
flaw)  in 

season 

at  rates 

less  than 

1,900 

w^tcr  in 
acre-feet 

reservoir 
surface 

in 
acre-feet 

second- 
feet  of 
natural 
flow)  in 

season 

at  rates 

less  than 

1,900 

acre-feet 

second- 
feet  in 
acre-feet 

acre  feet 

second- 
feet  in 
acre-feet 

1897 

Jan. 

3,fil7 

0 

3,617 

0 

0 

0 

0 

0 

.      3.617 

0 

Feb. 

IS),  146 

0 

7,262 

4,913 

0 

0 

0 

0 

7.262 

0 

Mar. 

28.ti23 

6,971 

9,344 

0 

0 

0 

0 

11.884 

9.344 

0 

April 

17,511. 

26,250 

9,042 

0 

4.164 

131 

0 

31.163 

9,042 

0 

May 

8,8.51 

3C,432 

8,126 

0 

5,963 

194 

0 

34,.53o 

8.120 

0 

.June 

4,033 

25,000 

4,033 

0 

5,985 

206 

0 

28.236 

4.033 

(1 

J  lily 

2,343 

18,800 

2,343 

0 

6.185 

212 

0 

21,244 

2.343 

0 

A,1K. 

1,1)'? 

12,412 

1,613 

0 

6,185 

149 

0 

14,020 

1.613 

0 

Sept. 

1,226 

6,078 

1,226 

0 

6.006 

72 

0 

6,855 

1.226 

0 

Oct. 

5,564 

0 

2,622 

0 

0 

0 

0 

0 

2,622 

0 

Nov. 

1,800 

2,942 

1,860 

0 

0 

20 

0 

2,942 

1.860 

0 

Dec. 

1,875 

2,922 

1,875 

0 

0 

0 

0 

2.922 

1.875 

0 

Total  or 
average 

96,270 

52,963 

1.013 

34,488 

984 

0 

52,963 

0 

1898 

.Jan. 

•2,453 

2.922 

2,453 

0 

0 

0 

0 

2.922 

2.453 

0 

Feb. 

2,241 

2,922 

2.241 

0 

0 

0 

0 

2,922 

2.241 

0 

Mar. 

2,131 

2,922 

2,131 

0 

0 

0 

0 

2.922 

2,131 

0 

April 

l,!»50 

2,922 

1,950 

0 

448 

34 

0 

2,922 

1,950 

(1 

May 

2,213 

2,440 

2,213 

0 

462 

39 

0 

2,440 

2,213 

0 

June 

1,1.5'.; 

1,93!! 

1,159 

0 

448 

39 

0 

1.939 

1.159 

0 

July 

672 

1,4.52 

672 

0 

464 

40 

0 

1.452 

o72 

0 

Aug. 

45fi 

948 

456 

0 

462 

26 

0 

948 

456 

0 

Sept. 

467 

460 

467 

0 

44b 

12 

c 

460 

467 

0 

Oct. 

5.33 

0 

533 

0 

0 

0 

0 

0 

533 

0 

Nov. 

.580 

0 

580 

0 

0 

0 

0 

0 

580 

0 

Dec. 
Total  or 
average 

832 

0 

832 

0 

0 

0 

0 

0 

832 
15,o87 

0 

15,687 

15,687 

0 

2.732 

190 

0 

n 

1899 

Jan. 

1, 114 

0 

1,414 

0 

0 

0 

0 

0 

1,114 

n 

Feb. 

1.244 

0 

1,244 

0 

0 

t 

0 

0 

1.244 

(1 

Mar. 

1.623 

0 

1,623 

0 

0 

0 

0 

0 

1.623 

0 

April 

1.262 

0 

1,262 

0 

0 

0 

0 

0 

1,262 

0 

May 

842 

0 

842 

0 

0 

0 

0 

0 

842 

(i 

June 

565 

0 

565 

0 

0 

0 

0 

0 

o65 

11 

July 

221 

0 

221 

0 

0 

0 

0 

0 

221 

0 

Auk. 

205 

0 

295 

0 

0 

0 

0 

0 

295 

(I 

Sept. 

220 

0 

220 

0 

0 

0 

0 

0 

220 

(1 

Oct. 

683 

0 

683 

0 

0 

0 

0 

0 

683 

0 

Nov. 

847 

0 

847 

0 

0 

0 

0 

0 

847 

(I 

Dec. 

1,247 

0 

1,247 

0 

0 

0 

0 

0 

1,247 

0 

Total  or 
averaKC 

10.463 

0 

0 

10,403 

»l 

0 

10,463 

0 

i 


THE   CONTROL    OF    FLOODS    BY    KESEKVOIRS. 

VOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

ONAL  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  12,  page  158.) 


361 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000  acre 

-feet  capacity 

Flood 

control 

Passed 

water 

Seisonally 
stored 

Evapora- 
tion 
from 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

cf 
month  in 
acre-feet 

by  dam 
for  prior 

rights 
(first  152 

passing 
Azusa 
d.iring 
flood 

Seasonally 
stored 

Evapora- 
tion 
from 

Waste 
over 

Year  and 
month 

water  in 
acre-feet 

reservoir 
surface 

in 
acre-feet 

second- 
feet  of 
natiiral 
flow)  in 

season 

at  rates 

less  than 

1,900 

water  in 
acre-feet 

reservoir 
Siirface 

in 
acre-feet 

spillway 

in 
acre-feet 

acre-feet 

second- 
feet  in 
acre-feet 

1897 

0 

0 

0 

0 

3,617 

0 

0 

0 

0 

Jan. 

0 

0 

n 

0 

7,262 

0 

0 

0 

0 

Feb. 

0 

0 

0 

11,884 

9,344 

0 

0 

0 

0 

Mar. 

4,y5S 

147 

0 

31,163 

9,042 

0 

4,958 

147 

0 

April 

6,814 

210 

0 

34,535 

8,126 

0 

6,814 

210 

0 

May 

6,770 

999 

0 

28,236 

4,033 

0 

6,770 

222 

0 

June 

6,996 

228 

0 

21,244 

2,343 

0 

6,996 

228 

0 

.  July 

6,996 

169 

0 

14,020 

1,613 

0 

6,996 

169 

0 

Aug. 

6,770 

85 

0 

6,855 

1,226 

0 

6,770 

85 

0 

Sett. 

0 

0 

0 

0 

2,622 

0 

0 

0 

0 

Oct. 

0 

20 

0 

2,942 

1,860 

0 

0 

20 

0 

Nov. 

0 

0 

0 

2,922 

1,875 

0 

0 

0 

0 

Dec. 
Total  or 
average 

39,304 

1,081 

0 

52,963 

0 

39,304 

1,081 

0 

1898 

0 

0 

0 

2,922 

2,i53 

0 

0 

0 

0 

Jan. 

0 

0 

0 

2,922 

2,241 

0 

0 

0 

0 

Feb. 

0 

0 

0 

2,922 

2,131 

0 

0 

0 

0 

Mar. 

448 

3* 

0 

2,922 

1,950 

0 

448 

34 

0 

April 

462 

39 

0 

2,440 

2,213 

0 

462 

39 

0 

May 

448 

39 

0 

1.939 

1,159 

0 

448 

39 

0 

June 

464 

40 

0 

1,452 

6/2 

0 

464 

40 

0 

July 

462 

26 

0 

948 

456 

0 

462 

26 

0 

-■Vug. 

448 

12 

0 

460 

467 

0 

448 

12 

0 

Sept. 

0 

0 

0 

0 

533 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

580 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

832 

0 

0 

0 

0 

Dec. 
Total  or 

average 

2,732 

190 

0 

15,687 

0 

2,732 

190 

0 

1899 

0 

0 

0 

0 

1,414 

0 

0 

0 

0 

Jan. 

(1 

0 

0 

0 

1,244 

0 

0 

0 

0 

Feb. 

0 

0 

0 

0 

1,623 

0 

0 

0 

0 

Mar. 

0 

0 

0 

0 

1,262 

0 

0 

() 

0 

April 

0 

0 

0 

0 

842 

0 

0 

0 

0 

May 

(1 

0 

0 

0 

565 

0 

0 

0 

0 

June 

0 

0 

0 

n 

221 

0 

(1 

0 

0 

July 

0 

0 

0 

0 

295 

0 

0 

0 

0 

Aug. 

0 

0 

0 

0 

220 

0 

0 

0 

0 

Sept. 

0 

0 

0 

0 

683 

n 

0 

0 

0 

Oct. 

0 

0 

0 

0 

847 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

1,247 

0 

0 

0 

0 

Dec. 
Total  or 
average 

0 

0 

0 

10,463 

0 

0 

0 

0 

■.W2 


NVATEI{    RESOURCES   OF    CALIFORNIA. 


TABLE  12a  ^Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL  AND  SEAS 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  control  reserve  or  first 

180,000  acre- 

131,000  acre-feet  of  capacity 

Flood 

Flood 

control 

control 

Run-off 

at 
Azusa 

Passed 

water 

Passed 

water 

Year  and 
month 

Stage  of 
reservoir 

tydam 

for  nrior 

rights 

passing 
Azusa 
during 

Seasonally 

Evapora- 
tion 
from 

Waste 

Stage  of 
reser^'oir 

by  dam 

for  prior 

rights 

passing 
.\zu8a 
during 

in 
acre-feet 

at 
beginning 

of 
month  in 
acre-feet 

(first  152 
second- 

flood 
season 

stored 
water  in 

reservoir 
svirface 

in 
acre-feet 

over 
spillway 

at 
beginning 

of 
month  in 
acre-feet 

(first  152 
second- 

flood 
season 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1.900 

acre-feet 

in 
acre-feet 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1,900 

acre-feet 

eecond- 
feet  in 

acre-feet 

second- 
feet  in 

acre-feet 

acre-feet 

1900 

Jan. 

1,S68 

0 

1,968 

0 

0 

0 

0 

0 

1.968 

0 

Feb. 

I.IU 

0 

1,111 

0 

0 

0 

0 

0 

1,111 

0 

Mar. 

1,230 

0 

1,230 

0 

0 

0 

0 

0 

1.230 

0 

April 

1.012 

0 

1,012 

0 

0 

0 

0 

0 

1.012 

0 

May 

2.275 

0 

2,275 

0 

0 

0 

0 

0 

2.275 

0 

June 

893 

0 

893 

0 

0 

0 

0 

0 

893 

0 

July 

369 

0 

369 

0 

0 

0 

0 

0 

369 

0 

Aug. 

246 

0 

246 

0 

0 

0 

0 

0 

246 

0 

Sept. 

238 

0 

238 

0 

0 

0 

0 

0 

238 

0 

Oct. 

307 

0 

307 

0 

0 

0 

0 

0 

307 

0 

Nov. 

11,068 

0 

1,058 

0 

0 

0 

0 

0 

1,058 

0 

Dec. 
Total  or 
average 

1,269 

10,010 

1,269 

0 

0 

0 

0 

10,010 

1.269 

0 

21,986 

11,976 

0 

0 

0 

0 

11.970 

0 

1901 

Jan. 

10.391 

10,010 

6,661 

12,810 

0 

0 

0 

10,010 

6,661 

0 

Feb. 

38,709 

930 

8,350 

19,884 

0 

0 

0 

13.740 

8,3.50 

0 

Mar. 

13,589 

11,405 

9,138 

0 

0 

0 

0 

44,099 

9,1.38 

0 

April 
May 

6,545 

15,856 

6,545 

0 

2.499 

99 

0 

48,550 

6,545 

0 

7,440 

13,258 

6,990 

0 

2,582 

117 

0 

tO,600 

6,990 

0 

June 

3,749 

11,009 

3,749 

0 

2,618 

129 

0 

32,799 

3,749 

0 

July 

1,845 

8,202 

1,845 

0 

2,704 

125 

0 

24,679 

1.845 

0 

Aug. 

1,240 

5,433 

1,240 

0 

2,704 

79 

0 

16,295 

1.240 

0 

Sept. 

1,012 

2,650 

1.012 

0 

2,610 

40 

0 

7.971 

1.012 

0 

Oct. 

1,476 

0 

1,476 

0 

0 

0 

0 

0 

1.476 

0 

Nov. 

1,904 

0 

1,904 

0 

0 

0 

0 

0 

1.904 

0 

Dec. 

1,600 

0 

1,660 

0 

0 

0 

0 

0 

1.660 

0 

Total  or 

average 

89,560 

50.570 

32.694 

15,;i7 

589 

0 

50.570 

0 

1902 

Jan. 

1,722 

0 

1,722 

0 

0 

0 

0 

0 

1.722 

0 

Feb. 

2,055 

0 

2.055 

0 

0 

0 

0 

0 

2.055 

(1 

Mar. 

6,088 

0 

5,590 

0 

0 

0 

0 

0 

5.590 

0 

April 
May 

3,928 

498 

3,928 

0 

72 

8 

0 

498 

3.928 

0 

2,398 

418 

2,398 

0 

73 

11 

0 

418 

2.398 

0 

June 

1,190 

334 

1,190 

0 

72 

12 

0 

334 

1.190 

0 

July 

076 

250 

676 

0 

74 

12 

0 

250 

676 

0 

Aug. 

430 

164 

430 

0 

74 

12 

0 

164 

430 

0 

Sept. 

298 

78 

298 

0 

72 

6 

0 

78 

298 

0 

Oct. 

430 

0 

430 

0 

0 

0 

0 

0 

430 

0 

Nov. 

1,131 

0 

1,131 

0 

0 

0 

0 

0 

1.131 

0 

Dec. 

1,968 

0 

1,968 

0 

0 

0 

0 

0 

1.968 

0 

Total  or 
average 

22.314 

21,816 

0 

437 

61 

0 

21,816 

0 

THE    CONTROL   OF    FLOODS    BY    RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

''COORDINATED  PLAN." 

ONAL  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  sec  Tabic  12,  page  158.) 


363 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  cppacity 

240,000  acre 

-feet  capacity 

Flood 

control 

Passed 

water 

Seasonally 
stored 
water  in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

by  dam 
for  prior 

rights 
(first  152 
second- 
feet  of 

passing 
Azusa 

during 
flood 

season 

at  rates 

Seasonally 
stored 
water  in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

Waste 

over 

spillway 

in 
acre-feet 

Year  and 
itomth 

in 
acre-feet 

natural 
flow)  in 

less  than 
1,900 

in 
acre-feet 

acre-feet 

second- 
feet  in 

acre-feet 

1900 

0 

0 

0 

0 

1,968 

0 

0 

0 

0 

Jan. 

0 

U 

0 

0 

1,111 

0 

0 

0 

0 

Feb. 

0 

0 

0 

0 

1,230 

0 

0 

0 

0 

Mar. 

0 

0 

0 

0 

1,012 

0 

0 

0 

0 

April 

0 

0 

0 

0 

2,2V5 

0 

0 

0 

0 

May 

0 

0 

0 

0 

893 

0 

0 

0 

0 

June 

0 

0 

0 

0 

369 

0 

0 

0 

0 

July 

0 

0 

0 

0 

246 

0 

0 

0 

0 

Aug. 

0 

0 

0 

0 

238 

0 

0 

0 

0 

Sept. 

0 

0 

0 

0 

30  < 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

1,058 

0 

0 

0 

0 

Nov. 

0 

0 

0 

10,010 

1,269 

0 

0 

0 

0 

Dec. 

Total  or 
average 

0 

0 

0 

11,976 

0 

0 

0 

0 

1901 

0 

0 

0 

10,010 

6,861 

0 

0 

0 

0 

Jan. 

0 

0 

0 

13,740 

8,350 

0 

0 

0 

0 

Feb. 

0 

0 

0 

44,099 

9,138 

0 

0 

0 

0 

Mar. 

7.763 

187 

0 

48,550 

6,545 

0 

7,7'i3 

187 

0 

April 

8,023 

228 

0 

40,600 

6,990 

0 

8,023 

228 

0 

May 

'•        7,878 

242 

0 

32,799 

3,/49 

0 

7,878 

242 

0 

June 

;        8,140 

244 

0 

24,679 

],845 

0 

8,140 

244 

0 

July 

8,140 

.184 

0 

16,295 

1,240 

0 

8,140 

184 

0 

Aug. 

7,878 

93 

0 

7,971 

1,012 

0 

7,878 

93 

0 

Sept. 

'              0 

0 

0 

0 

1,4(6 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

1,904 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

1,660 

0 

0 

0 

0 

Dec. 
Total  or 
average 

4i,822 

1,178 

0 

50,570 

0 

47,822 

1,178 

0 

1902 

0 

0 

0 

0 

1,722 

0 

0 

0 

0 

Jan. 

0 

0 

0 

0 

2,055 

0 

0 

0 

0 

Feb. 

0 

0 

0 

0 

5,590 

0 

0 

0 

0 

Mar. 

(2 

8 

0 

498 

3,928 

0 

72 

8 

0 

April 

73 

11 

0 

418 

2,398 

0 

73 

11 

0 

May 

72 

12 

0 

334 

1,190 

0 

72 

12 

0 

.June 

74 

12 

0 

250 

676 

0 

74 

12 

0 

July 

74 

12 

0 

164 

430 

0 

74 

12 

0 

Aug. 

72 

6 

0 

78 

298 

0 

72 

6 

0 

Sept. 

0 

0 

0 

0 

430 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

1,131 

0 

0 

0 

0 

Nov. 

'              0 

0 

0 

0 

1,968 

0 

0 

0 

0 

Dec. 
Total  or 
average 

437 

61 

0 

21,816 

0 

437 

61 

(• 

364 


WATER   RESOURCES   OF    CALIEORXIA. 


TABLE  12a  (Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL  AND  SEAS 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1.900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  control  reserve  oi  first 

131.000  acre-feet  of  caperlty 

180,000  acre- 

Flood 

Flood 

control 

control 

Run-off 

Paesed 

water 

Passed 

water 

Year  and 
month 

at 
.Azusa 

Stage  of 

re.^ervoir 

at 

by  dam 

for  prior 

rights 

pissing 
Azusa 
during 

Season-illy 

Evapora- 
tion 

r-,^rn 

Waste 

Stage  of 
reservoir 

by  dam 

for  prior 

rights 

parsing 
.Azusa 
during 

acre-foet 

beginning 
of 

(first  152 
second- 

fljod 
season 

storefl 
water  in 

irom 
reservoir 
surface 

in 
acre-feet 

over 
spillway 

at 
beginning 

(first  1.52 
second- 

fljod 
season 

mouth  in 
acre-feet 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1.900 

acre-feet 

in 
acre-feet 

of 
month  in 
acre-feet 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1,900 

acre-feet 

second- 
feet  in 
acre-feet 

acre-feet 

second- 
feet  in 
acre-feet 

1903 

Jan. 

9,100 

0 

2,536 

4,856 

0 

0 

0 

0 

2  536 

0 

Feb. 

5,665 

1,708 

5.497 

1,189 

0 

0 

0 

6.554 

5.497 

0 

Mar. 

15,802 

687 

7,898 

0 

0 

0 

0 

6,732 

7,898 

0 

April 

47.127 

8,591 

9,042 

0 

1.344 

67 

0 

14,636 

9,042 

0 

May- 

13,343 

45,265 

9,116 

0 

8,963 

244 

0 

50.322 

9.116 

0 

June 

5,653 

40,285 

5,653 

0 

9,703 

272 

0 

44,322 

5,653 

(1 

July 

2,644 

30,310 

2,644 

0 

10,026 

270 

0 

33.358 

2.644 

0 

Aug. 

1.783 

20,014 

1,783 

0 

10,026 

202 

0 

22.039 

1.783 

0 

Sept. 

1,488 

9,786 

1.488 

0 

9,685 

101 

0 

10,789 

1.488 

0 

Oct. 

1,476 

0 

1,476 

0 

0 

0 

0 

0 

1.476 

0 

Nov 

1,428 

0 

1,428 

0 

0 

0 

0 

0 

1.428 

0 

Dec. 
Total  or 

1,476 

0 

1,476 

0 

0 

0 

0 

0 

1,476 

0 

average 

106,985 

50,037 

6,045 

49.747 

1,153 

0 

50,037 

0 

1904 

Jan. 

1,500 

0 

1.500 

0 

0 

0 

0 

0 

1,500 

0 

Feb. 

2,744 

0 

2,177 

0 

0 

0 

0 

0 

2. '77 

0 

Mar. 

6,813 

567 

4,724 

0 

0 

0 

0 

557 

4  724 

U 

April 

5,337 

?,653 

5,337 

0 

407 

19 

0 

2,658 

5,337 

0 

May 

4,08!' 

2,220 

4.089 

0 

420 

37 

0 

2,220 

4,089 

0 

June 

1,517 

1,763 

1,517 

0 

407 

36 

0 

1,763 

1,517 

(1 

July 

861 

1,329 

861 

0 

420 

3G 

0 

1.320 

861 

U 

Aug. 

793 

864 

793 

0 

420 

21 

0 

884 

793 

U 

Sept. 

643 

420 

643 

0 

408 

12 

0 

420 

6t3 

0 

Oct. 

7.38 

0 

738 

0 

0 

0 

C 

0 

738 

0 

Nov. 

762 

0 

762 

0 

0 

0 

0 

U 

762 

0 

Dec. 
Total  or 

l.a39 

0 

1,039 

0 

0 

0 

0 

0 

1,039 

0 

average 

26,836 

24.180 

0 

2.482 

174 

0 

21,180 

0 

190S 

Jan. 

2.251 

0 

2,251 

0 

0 

0 

0 

0 

2,251 

0 

Feb. 

25,880 

0 

8,206 

11.798 

0 

0 

0 

0 

8  206 

0 

Mar. 

75,140 

5.876 

0.281 

18.198 

0 

0 

0 

17.674 

9,281 

0 

.^pril 
May 

19.580 

53.537 

9.042 

0 

8,727 

197 

0 

8 1,533 

9,042 

0 

17,090 

55,151 

9.344 

0 

10,942 

271 

(1 

80,378 

9,344 

0 

June 

8,271 

51.681 

7,960 

0 

12.475 

313 

0 

71,790 

7,960 

0 

July 

5,103 

39,201 

5.103 

0 

12,y8a 

313 

0 

51,358 

5,103 

0 

Aug. 

2,631 

25,902 

2,631 

0 

12,989 

232 

0 

35,935 

2.631 

0 

Sept. 

1.869 

12.681 

1.869 

0 

12,560 

121 

0 

17,612 

1,8'J9 

0 

Oct. 

1,770 

0 

1.770 

0 

0 

0 

0 

0 

1,770 

0 

Nov. 

2,660 

0 

2,660 

0 

0 

0 

0 

0 

2  660 

0 

Dec. 
Total  or 

2.470 

0 

2.470 

0 

0 

0 

0 

0 

2,470 

0 

average 

164,715 

62,587 

29.996 

70,882 

1,450 

■   0 

62.587 

0 

THE    CONTROL   OF    FliOODS   BY    RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

ONAL  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  12,  page  158.) 


365 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

2'10,000  acre-feet  capacity 

Flood 

control 

Passed 

water 

t-oiEoually 

Evapora- 
tion 
from 

Waste 

Stage  of 
reservoir 

by  dam 

for  prior 

rignts 

passing 
Azusa 
during 

Seasomlly 

Evapora- 
tion 

Waste 

Year  and 
month 

stored 

o^er 
spillway 

in 
acre-feet 

at 
beginning 

of 
month  in 
acre-feet 

(first  152 

flood 

stored 

from 

over 

spillway 

in 

witcr  in 
acre-feet 

reservoir 
surface 

second- 
feet  of 

season 
at  rates 

water  in 
acre-feet 

reservoir 
surface 

in 
acre-feet 

nitural 
flnw)  in 

less  than 
1,900 

in 
acre-feet 

acre-feet 

acre-fee t 

second- 
feet  in 
acre-feet 

1903 

0 

0 

0 

0 

2,536 

0 

0 

0 

0 

Jan. 

0 

0 

0 

6  564 

5,497 

0 

0 

0 

0 

Feb. 

0 

0 

0 

6,732 

7,898 

0 

0 

0 

0 

Mar. 

2.304 

95 

0 

14,636 

9.042 

0 

2..304 

95 

0 

April 

9,969 

258 

0 

50,322 

9,116 

0 

9,969 

258 

0 

May 

10,676 

288 

0 

44,322 

5,653 

0 

10,676 

288 

0 

June 

11,030 

289 

0 

33,358 

2,644 

0 

11,030 

289 

0 

Jaly 

11,030 

220 

0 

22,039 

1,783 

0 

11,030 

220 

0 

.\ug. 

10,676 

113 

0 

10,789 

1,488 

0 

10.676 

113 

0 

Sept. 

0 

0 

0 

0 

1.476 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

1.428 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

1,476 

0 

0 

0 

0 

Dec. 

Total  or 
average 

55,685 

1,263 

0 

50,037 

0 

55,685 

1,263 

0 

1904 

0 

0 

0 

0 

1.500 

0 

0 

0 

0 

Jan. 

0 

0 

0 

0 

2,177 

0 

0 

0 

0 

Feb. 

0 

0 

0 

567 

4,724 

0 

0 

0 

0 

Mar. 

407 

29 

0 

2,656 

5,337 

0 

407 

29 

0 

April 

420 

37 

0 

2,220 

4,089 

0 

420 

37 

0 

May 

407 

3G 

0 

1,763 

1,517 

0 

407 

36 

0 

June 

420 

36 

0 

1,320 

861 

0 

420 

36 

0 

July 

420 

24 

0 

864 

793 

0 

420 

24 

0 

Aug. 

408 

12 

0 

420 

643 

0 

408 

12 

0 

Sept. 

0 

0 

0 

0 

738 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

762 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

1,039 

0 

0 

0 

0 

Dec. 
Total  or 
average 

2,482 

174 

0 

24,180 

0 

2,482 

174 

0 

1905 

0 

0 

0 

0 

2,251 

0 

0 

0 

0 

Jan. 

0 

0 

0 

0 

8.206 

0 

0 

0 

0 

Feb. 

0 

0 

0 

17,674 

9,281 

0 

0 

0 

0 

Mar. 

K!,429 

264 

0 

83,533 

9,042 

0 

13.429 

264 

0 

Apri! 

15,987 

347 

0 

80,378 

9.344 

0 

15,987 

347 

0 

May 

17,357 

386 

0 

71,790 

7,960 

0 

17.357 

386 

0 

June 

18,039 

384 

0 

54,358 

5,103 

0 

18,039 

384 

0 

July 

18,039 

284 

0 

35,935 

2,631 

0 

18,039 

284 

0 

Aug. 

17,459 

153 

0 

17.612 

1,869 

0 

17,459 

153 

0 

Sept. 

0 

0 

0 

0 

1,770 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

2,660 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

2,470 

0 

0 

0 

0 

Dec. 
Total  or 
average 

100.310 

1.818 

(1 

62.587 

0 

100,310 

1,818 

0 

366  WATEU   RESOURCES   OF    CALIFORNIA. 

TABLE  12a  (Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL  AND  SEAS 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  con 

trol  reserve  or  first 

IR 

131,000  acre-feet  of  capacity 

1  Ou,uuu   aiff  c- 

Flood 

Flood 

control 

control 

Run-off 

at 
Azusa 

Passed 

water 

Passed 

water 

Year  and 
month 

Stage  of 
reservoir 

by  dam 

for  prior 

rights 

papsing 
Azusa 
during 

Seasonally 

Evapora- 
tion 
from 
reservoir 
surface 

Waste 

Stage  of 
reservoir 

by  dam 

for  prior 

rights 

passing 
Azusa 
during 

in 
acre-fcct 

at 
beginning 

^first  152 
second- 

flood 
season 

stored 
water  in 

over 
spillway 

at 

beginning 

of 

(first  152 
second- 

flood 
season 

of 

feet  of 

at  rates 

acre  feet 

in 
acre-fcct 

month  in 
acre-feet 

feet  of 

at  rates 

month  in 
acre-feet 

natural 
flow)  in 

less  than 
1,900 

in 
acre-feet 

natural 
flow)  in 

less  than 
1,900 

acre-feet 

second- 
feet  in 
acre-feet 

acre  feet 

second- 
feet  in 
acre-feet 

1906 

Jan. 

4,240 

0 

3,633 

0 

0 

0 

0 

0 

3,633 

0 

Feb. 

.3,%0 

007 

3,960 

0 

0 

0 

0 

607 

3,960 

0 

Mar. 

129.000 

607 

7,561 

24,303 

0 

0 

0 

607 

7,561 

2,864 

April 

34,600 

97,743 

9,042 

19,634 

11.660 

274 

0 

119,182 

9,042 

0 

May 

21,000 

91,7.33 

9,344 

0 

18,263 

375 

0 

12.5.198 

9,344 

0 

June 

1.5,500 

84.751 

9,042 

0 

20,518 

426 

0 

111,414 

0,042 

0 

July 

9,3.50 

70,265 

8,664 

0 

22,606 

452 

0 

90.348 

8,664 

0 

Aug. 

4,490 

47,893 

4.490 

0 

24,086 

329 

0 

60,436 

4.490 

0 

Sept. 

2,840 

23,478 

2.840 

0 

23,305 

173 

0 

29,637 

2,840 

0 

Oct. 

2,450 

0 

2,450 

0 

0 

0 

0 

0 

2,4.50 

0 

Nov. 

2,400 

0 

2,400 

0 

0 

0 

0 

0 

2,400 

0 

Dec. 
Total  or 
average 

11,600 

0 

4,030 

0 

0 

0 

0 

0 

4,030 

0 

241,430 

67,456 

43,937 

120,4.38 

2,029 

0 

67,456 

2.864 

1907 

Jan. 

58,400 

7,570 

9,217 

50,881 

0 

0 

0 

7,570 

9,217 

1,881 

Feb. 

47,100 

5,872 

8,439 

31,125 

0 

0 

0 

54,872 

8.439 

31.125 

Mar. 

116,000 

13,408 

9,344 

47,166 

0 

0 

0 

62,408 

9,344 

47,166 

April 
May 

58,400 

72,898 

9,042 

0 

11,708 

238 

0 

121,898 

9,042 

0 

21, .500 

110,310 

9,344 

0 

21.989 

426 

0 

151,269 

9,344 

0 

June 

15,100 

100,051 

9,042 

0 

24,242 

478 

0 

1,32,686 

9,042 

0 

July 

8,360 

81,389 

7,920 

0 

27,072 

493 

0 

105,969 

7,920 

0 

Aug. 

5,390 

54.264 

5,390 

0 

27,300 

359 

0 

70,528 

5,390 

0 

Sept. 

3,580 

26,605 

3,580 

0 

26,421 

184 

0 

34,589 

3,580 

0 

Oct. 

4,090 

0 

4,090 

0 

0 

0 

0 

0 

4,090 

0 

Nov. 

3,800 

0 

3,800 

0 

0 

0 

0 

0 

3.800 

0 

Dec. 
Total  or 
average 

3.600 

0 

3,600 

0 

0 

0 

0 

0 

3,600 

0 

345,320 

82,808 

129,172 

138.732 

2,178 

0 

82,808 

80,172 

1808 

Jan. 

11,100 

0 

4,973 

4.617 

0 

0 

0 

0 

4,973 

0 

Feb. 

15,000 

1.510 

8.741 

5,141 

0 

0 

0 

6,127 

8,741 

0 

Mar. 

12,700 

2.628 

9,255 

0 

0 

0 

0 

12,386 

9,2.55 

0 

April 
May 

9,280 

6,073 

8,656 

0 

952 

52 

0 

15,831 

8,656 

0 

7,190 

5,693 

7,139 

0 

1,106 

69 

0 

13.860 

7,139 

(1 

June 

4,190 

4,569 

4,190 

0 

1,071 

61 

0 

11,067 

4,190 

0 

July 

2,560 

3,437 

2,560 

0 

1,106 

57 

0 

8.309 

2,560 

0 

Aug. 

2,210 

2,274 

2,210 

0 

1,106 

36 

0 

5,405 

2,210 

0 

Sept. 

1,820 

1,132 

1.820 

0 

1,120 

12 

(1 

2,665 

1,820 

0 

Oct. 

2.070 

0 

2,070 

0 

0 

0 

0 

0 

2.070 

0 

Nov. 

1.960 

0 

1,960 

0 

0 

0 

0 

0 

1,960 

0 

Dec. 
Total  or 
average 

2.870 

0 

2.870 

0 

0 

0 

0 

0 

2,870 

0 

72.950 

56,444 

0,758 

6,461 

287 

0 

56,444 

0 

THE    CONTROL   OF    FLOODS   BY    RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

ONAL  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  12,  page  158.) 


367 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000  acre 

■feet  capacity 

Flood 

control 

Passed 

water 

Seasonally 
stored 
water  in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

Waste 

over 

spillway 

in 

Stage  of 
reservoir 

at 

beginning 

of 

by  dam 
for  prior 

righto 
(first  152 
seconH- 

fect  of 

passing 
Azusa 

during 
flood 

season 

at  rates 

Seasonally 
stored 
water  in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

Waste 

over 

spillway 

in 

Year  and 
month 

in 
acre-feet 

acre-feet 

month  in 
acre-feet 

natural 
flow)  in 
acre-feet 

less  than 

1,900 
second- 
feet  in 

acre-feet 

in 
acre-feet 

acre-feet 

190S 

0 

0 

0 

0 

3,633 

0 

0 

0 

0 

.Jan. 

0 

0 

0 

607 

3,960 

0 

0 

0 

0 

Feb. 

0 

0 

0 

607 

7,561 

0 

0 

0 

0 

Mar. 

19,209 

333 

0 

122,046 

9,042 

0 

19,673 

339 

0 

April 

24,974 

466 

0 

127,.592 

9,344 

0 

25,454 

472 

0 

May 

27,008 

516 

0 

113,322 

9,042 

0 

27,481 

492 

0 

June 

30,069 

529 

0 

91,807 

8,664 

0 

30,557 

535 

0 

July 

30,416 

383 

0 

61,401 

4,490 

0 

30,906 

385 

0 

Aug. 

29,437 

200 

0 

30,110 

2,840 

0 

29,910 

200 

0 

Sept. 

0 

0 

0 

0 

2,4.50 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

2,400 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

4,030 

0 

0 

0 

0 

Dec. 
Total  or 
a\erage 

161,113 

2,427 

0 

67,456 

0 

163,981 

2,423 

0 

1907 

0 

0 

0 

7,570 

9,217 

0 

0 

0 

0 

.Jan. 

0 

0 

0 

56,753 

8,439 

0 

0 

0 

0 

Feb. 

0 

0 

0 

95,414 

9,344 

20,172 

0 

0 

0 

Mar. 

19,650 

337 

0 

181,898 

9,012 

0 

29,388 

446 

0 

April 

30,209 

530 

0 

201,422 

9,344 

0 

40,265 

650 

0 

May 

32,194 

.581 

0 

172,663 

9,042 

0 

41,941 

700 

0 

June 

35,292 

589 

0 

136,080 

7,920 

0 

45,367 

698 

0 

July 

35,517 

422 

0 

90,455 

5,390 

0 

45,589 

496 

0 

Aug. 

34,371 

218 

0 

44,370 

3,580 

0 

44,122 

248 

0 

Sept. 

0 

0 

0 

0 

4,090 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

3,800 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

3,600 

0 

0 

0 

0 

Dec. 
Total  or 
average 

187,233 

2,677 

0 

82,808 

20,172 

246,672 

3,238 

0 

190S 

0 

0 

0 

0 

4,9/3 

0 

0 

0 

0 

Jan. 

0 

0 

0 

6,127 

8,741 

0 

0 

0 

0 

Feb. 

0 

0 

0 

12,386 

9,2.55 

0 

0 

0 

0 

Mar. 

2,496 

09 

0 

15,831 

8,656 

0 

2,496 

99 

0 

April 

2,721 

123 

0 

13,860 

7,139 

0 

2,721 

123 

0 

May 

2,623 

135 

0 

11,007 

4,190 

0 

2,623 

135 

0 

June 

2,711 

133 

0 

8,309 

2,560 

0 

2,711 

1.33 

0 

July 

2,711 

89 

0 

5,465 

2,210 

0 

2,711 

89 

0 

Aug. 

2,625 

40 

0 

2,665 

1,820 

0 

2,625 

40 

0 

Sept. 

0 

(1 

0 

0 

2,070 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

1,960 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

2,870 

0 

0 

0 

0 

Dec. 
Total  or 
average 

15.887 

619 

0 

56,444 

0 

1.5,887 

619 

( 

;{68 


WATEIt    KESOUHCES   OK    CALIFOKNIA. 


TABLE  12a  (Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL  AND  SEAS 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  finod  cor 

trol  reserve  or  first 

131,000  acre-feet  of  capacity 

ISu.uuu  acre- 

Flood 

Flood 

control 

control 

Year  and 
month 

Run-off 

at 
Azusa 

Stage  of 
rsservnir 

Pasped 

by  dam 

for  prior 

rights 

water 
passing 

Azusa 
during 

Seasonally 

Evapora- 
tion 

Waste 

Stage  of 
reservoir 

Passed 

by  dam 

for  prior 

rights 

water 
pissing 

Azusa 
during 

in 
acre-fee t 

at 
beginninK 

of 
month  in 
acre-feet 

(first  152 

flood 

stored 

trom 

over 

at 

(first  152 

flood 

second- 
feet  of 

season 
at  rates 

water  in 
acre-feet 

Ti^servoir 
surface 

spillway 

in 
acre-feet 

beginning 

of 
month  in 
acre-feet 

second- 
feet  of 

season 
at  rates 

natural 
flow)  in 

less  than 
1,900 

in 
acre-feet 

natural 
flow)  in 

less  than 
1.900 

acre-feet 

second- 
feet  in 

acre-feet 

second- 
feet  in 

acre-feet 

acre-feet 

1909 

Jan. 

2,5,500 

0 

5,.596 

19,385 

0 

0 

0 

0 

5.596 

0 

Feb. 

.50,400 

519 

8,440 

42,858 

0 

0 

0 

19,904 

8,440 

13.213 

Mar. 

2t).300 

8,621 

9,,344 

0 

0 

0 

0 

57,621 

9,344 

0 

April 

28,000 

25,577 

9,042 

0 

4,063 

131 

0 

74,577 

9,012 

0 

May 

15,200 

40,341 

9,344 

0 

7,980 

228 

0 

81,312 

9,344 

0 

June 

8,570 

37.989 

8,319 

0 

9,144 

260 

0 

70.645 

8,319 

0 

July 

5,010 

28,83ti 

5.040 

0 

9,528 

264 

0 

53.434 

5,040 

0 

Aug. 

3,120 

19,044 

3,120 

0 

9,528 

196 

0 

35,323 

3,120 

0 

Sept. 

2..?20 

9,320 

2,320 

0 

9,225 

r5 

0 

17,314 

2,320 

0 

Oct. 

2.310 

0 

2,310 

0 

0 

0 

0 

0 

2,310 

0 

Nov. 

2,880 

0 

2,880 

fl 

0 

0 

0 

0 

2,880 

0 

Dec. 

Total  or 

20,903 
199,510 

0 

6,346 

0 

0 

0 

0 

0 

6,346 

0 

averaRc 

72,101 

62,243 

49.468 

1,174 

0 

72,101 

13,243 

1910 

Jan. 

09,500 

14,554 

9,344 

73„583 

0 

0 

0 

14,5.54 

9,344 

24.583 

Feb. 

11,500 

1,127 

8,435 

2,()89 

0 

0 

0 

50,127 

8,435 

2,689 

Mar. 

9,590 

I, .503 

9,029 

0 

0 

0 

0 

50,503 

9,029 

0 

April 

8,270 

2,064 

8,120 

0 

321 

22 

0 

61.064 

8,120 

0 

May 

5,050 

1,871 

5,050 

0 

363 

29 

0 

42,847 

5,050 

0 

June 

3  560 

1,479 

3,560 

0 

352 

14 

0 

34,134 

3.560 

0 

July 

2,450 

1,113 

2,450 

0 

363 

16 

0 

25,684 

2.450 

0 

Aug. 

1,710 

734 

1.710 

0 

363 

16 

0 

16,957 

1,710 

0 

Sept. 

1,370 

355 

1,370 

0 

355 

0 

0 

8,294 

1.370 

0 

Oet. 

1,560 

0 

1,560 

0 

0 

0 

0 

0 

1,560 

0 

Nov. 

1.870 

0 

1,870 

0 

0 

0 

0 

0 

1,870 

0 

Dee. 
Total  or 

2.020 

0 

2,020 

0 

0 

0 

0 

0 

2,020 

0 

averaRe 

118.4.50 

54,518 

76,272 

2,117 

97 

0 

54,518 

27.272 

1911 

Jan. 

37,200 

fl 

6,441 

7,031 

0 

0 

0 

0 

6,441 

0 

Feb. 

44,300 

23,728 

S,440 

53,874 

0 

0 

0 

30.759 

8,140 

11.905 

Mar. 

122.000 

5,714 

9,344 

57,431 

0 

0 

0 

5J.714 

9,344 

57,434 

.Aj.ril 
Nlay 

28,230 

60,936 

9,012 

0 

9.774 

212 

0 

109,036 

9,042 

0 

16,600 

70,108 

9.344 

0 

13.936 

317 

0 

111,071 

9,344 

(I 

June 

7.500 

63,111 

7,322 

0 

15.247 

357 

0 

95,757 

7,322 

(1 

July 

5,230 

47,li85 

5,230 

0 

15,816 

355 

0 

72,274 

5.230 

0 

Aug. 

3.610 

31,514 

3,610 

0 

15.816 

2!0 

0 

47,786 

3,610 

0 

Sept. 

2.830 

15,4.38 

2,830 

0 

15,303 

i:;5 

0 

23,427 

2,830 

0 

Oct. 

3  140 

0 

3,140 

0 

0 

0 

0 

0 

3,14U 

0 

Nov. 

2.800 

0 

2,800 

0 

0 

0 

0 

0 

2,800 

1) 

Dec. 

2.870 

0 

2  870 

0 

0 

0 

0 

0 

2,870 

0 

Total  or 

270,280 

70,413 

average 

118.330 

8.'>.802 

1.0>36 

0 

70.413 

69,339 

THE    CONTROL   OP    FLOODS    BY    KE8ERV0IKS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

ONAL  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  12,  page  158.) 


369 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

■ 

240,000  acre-feet  capacity 

Flood 

control 

Passed 

water 

Evapora- 

Stage of 

by  dam 
for  prior 

pissing 
Azusa 

Evapora- 

Waste 

Year  and 

Se.iaoiially 

tion 
from 

Waste 

r3s?rvoir 

rishts 

during 

Seisonally 

tion 

month 

stored 

over 

at 

(first  152 

flood 

stored 

from 

over 
spillw.iy 

in 
acre-feet 

Witer  in 
acre-fee  t 

reservoir 
surface 

in 
acre-feet 

spillw.iy 

in 
acre-feet 

bRi^inning 

of 
month  in 
acre-feet 

second- 
feet  of 
natural 
fliw)  in 

season 

at  rates 

less  than 

1,900 

water  in 
acre-feet 

reservoir 
surface 

in 
acre-feet 

acre-feet 

second- 
feet  in 
acre-feet 

1903 

0 

0 

0 

0 

5.596 

0 

0 

0 

0 

,Ia... 

0 

0 

0 

19,904 

8,440 

0 

0 

0 

0 

Feb. 

0 

0 

0 

70,864 

9,344 

0 

0 

0 

0 

Mar. 

11,979 

244 

0 

87,820 

9.012 

0 

14,127 

272 

0 

Anrii 

16,174 

349 

0 

92,379 

9,344 

0 

18,392 

381 

0 

May 

17,079 

383 

0 

79,462 

8,319 

0 

19,225 

414 

0 

.June 

17,731 

.380 

0 

60,074 

5,040 

0 

19,949 

410 

0 

July 

17.7-31 

278 

0 

.39,715 

3.120 

0 

19,949 

295 

0 

Aug. 

17,165 

149 

0 

19,471 

2,320 

0 

19,314 

157 

0 

Sept. 

0 

0 

0 

0 

2,310 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

2,880 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

6,346 

0 

0 

0 

0 

Dee. 

Total  or 

97,859 

1,783 

0 

72,101 

0 

110,956 

1,929 

0 

average 
1910 

0 

0 

0 

14., 551 

9.344 

0 

0 

0 

0 

.Jan. 

0 

0 

0 

74,710 

8,435 

0 

0 

0 

0 

Feb. 

0 

0 

0 

77,775 

9,029 

0 

0 

0 

0 

Mar. 

8.174 

193 

0 

78,336 

8,120 

0 

12,.588 

2.50 

0 

April 

8,475 

2.38 

0 

65,648 

5,050 

0 

13,036 

306 

0 

May 

8,202 

248 

0 

52,306 

3,560 

0 

12,616 

317 

0 

June 

8,475 

252 

0 

.39,373 

2,450 

0 

13,036 

317 

0 

.lulv 

8,475 

188 

0 

26,020 

1,710 

0 

13,036 

238 

0 

Aug 

8,199 

95 

0 

12,746 

1,370 

0 

12,625 

121 

0 

Sept. 

0 

0 

0 

0 

1,560 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

1,870 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

2,020 

0 

0 

0 

0 

Dec. 

Total  or 

50,000 

1,214 

0 

51,518 

0 

76,937 

1,519 

0 

average 
1911 

0 

0 

0 

0 

6,441 

0 

0 

0 

0 

.Ian. 

0 

0 

0 

30,759 

8,440 

0 

0 

0 

0 

Feb. 

0 

0 

0 

6K.619 

9,344 

10,977 

0 

0 

0 

Mar. 

17,708 

315 

0 

168.2!)8 

9.042 

0 

27,179 

423 

0 

April 

22,142 

428 

0 

159,854 

9.344 

0 

31,928 

,551 

0 

May 

23.1P5 

466 

0 

134.631 

7,322 

0 

32,670 

585 

0 

.June 

24,026 

462 

0 

101. ,5,54 

5.230 

0 

33,815 

573 

0 

.July 

24,026 

.333 

0 

67,166 

3.610 

0 

33.815 

408 

0 

Aug. 

23.2.50 

177 

0 

32.943 

2.830 

0 

32,733 

210 

0 

Sept. 

0 

0 

0 

0 

3,140 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

2,800 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

2.870 

0 

0 

0 

0 

J)ec. 
Total  or 

134,.347 

2,181 

0 

70.113 

10.977 

192.110 

2,759 

0 

average 

,'570  "VVATEH   RESOURCES   OF    CALIFORNIA. 

TABLE  12a  (Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL  AND  SEAS 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  control  reserve  or  first 

180,000  acre- 

131,000  acre-feet  of  capacity 

Flood 

Flood 

control 

control 

Run-off 

at 
Azusa 

Passed 

water 

Passed 

water 

Year  and 
mopth 

Stage  nf 
reservoir 

at 
beginning 

by  dam 

for  prior 

rights 

passing 
Azusa 
during 

Seasonally 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 

Stage  of 
reservoir 

by  dam 

for  prior 

rights 

passing 
Azusa 
during 

in 
acre-feet 

(first  152 
second- 

flood 
season 

stored 
water  in 

over 
spillway 

at 
beginning 

ffirst  152 
second- 

flood 
season 

ot 
month  in 
acre-feet 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1,900 

acre-feet 

in 
acre-feet 

of 
month  in 
acre-feet 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1,900 

acre-feet 

second- 
feet  in 
acre-feet 

acre-feet 

second- 
feet  in 
acre-feet 

1912 

Jan. 

2,710 

0 

2,710 

0 

0 

0 

0 

0 

2.710 

0 

Feb. 

2,230 

0 

2,230 

0 

0 

0 

0 

0 

2.230 

0 

Mar. 

22,900 

0 

8,199 

0 

0 

0 

0 

0 

8.199 

0 

April 

18,000 

14,701 

8.515 

0 

2.314 

95 

0 

14.V01 

8,515 

0 

May 

10,900 

21,777 

8.828 

0 

4,273 

163 

0 

21,777 

8,828 

0 

June 

4,990 

19,413 

4,990 

0 

4,634 

182 

0 

19,413 

4,990 

0 

July 

3,060 

14,597 

3,060 

0 

4,790 

184 

0 

14.597 

3,060 

0 

Aug. 

1,960 

9,623 

1,960 

0 

4,790 

135 

0 

9,623 

1.960 

0 

Sept. 

1,550 

4,698 

1,550 

0 

4,634 

64 

0 

4,698 

1,.550 

0 

Oct. 

1,830 

0 

1,830 

0 

0 

0 

0 

0 

1,830 

0 

Nov. 

1,730 

0 

1,730 

0 

0 

0 

0 

0 

1.730 

0 

Dec. 

1.760 

0 

1.760 

0 

0 

0 

0 

0 

1.760 

0 

Total  or 
average 

73,620 

47.362 

0 

25,435 

823 

0 

47.362 

0 

1913 

Jan. 

2,910 

0 

2,910 

0 

0 

0 

0 

0 

2.910 

0 

Feb. 

13,200 

0 

4.753 

0 

0 

0 

0 

0 

4,753 

0 

Mar. 

10,200 

8,447 

8.759 

0 

0 

0 

0 

8.447 

8.759 

0 

April 
May 

7.140 

9,888 

7,091 

0 

1„547 

75 

0 

9.888 

7,091 

0 

4,970 

8.315 

4,970 

0 

1,608 

93 

0 

8.315 

4,970 

0 

June 

2,890 

6,614 

2.890 

0 

1.557 

95 

0 

6.614 

2,890 

0 

July 

1.690 

4.962 

1.690 

0 

1,607 

93 

0 

4,962 

1.690 

0 

Aug. 

1.070 

3.262 

1,070 

0 

1,607 

68 

0 

3,202 

1,070 

0 

Sept. 

893 

1.587 

893 

0 

1,555 

32 

0 

1,587 

893 

0 

Oct. 

910 

0 

910 

0 

0 

0 

0 

0 

910 

0 

Nov. 

2.280 

0 

2,280 

0 

0 

0 

0 

0 

2,280 

0 

Dec. 

Total  or 

2.170 

0 

2,170 

0 

0 

0 

0 

0 

2.170 

0 

average 

50.323 

40,386 

0 

9.481 

456 

0 

40.386 

0 

1914 

Jan. 

61.400 

0 

6,271 

41,989 

0 

0 

0 

0 

6,271 

1.248 

Feb. 

121,000 

13,140 

8,440 

.59.505 

0 

0 

0 

53.881 

8,440 

51.246 

Mar. 

48,000 

66,195 

9,344 

53,083 

0 

0 

0 

115.195 

9.344 

53,083 

April 
May 

21,400 

51,768 

9,042 

0 

8.291 

193 

0 

100,768 

9,042 

1) 

16,900 

55.642 

".'.344 

0 

11,077 

274 

0 

96.603 

9,344 

0 

June 

9,580 

51.847 

8,585 

0 

12.509 

313 

0 

81,529 

8,585 

() 

July 

5,570 

40.020 

5,570 

0 

13,258 

317 

0 

64,634 

5,570 

0 

Aug. 

3,630 

26,445 

3,630 

0 

13.258 

238 

0 

42,731 

3.630 

0 

Sept. 

2.730 

12.949 

2,730 

0 

12.826 

123 

0 

20.945 

2.V30 

0 

Oct. 

2.770 

0 

2.770 

0 

0 

0 

0 

0 

2,770 

0 

Nov. 

2.440 

0 

2,440 

0 

0 

0 

0 

0 

2,440 

0 

Dec. 
Total  or 

4,290 

0 

4,290 

0 

0 

0 

0 

0 

4,290 

0 

average 

299,710 

72,456 

154,577 

71.219 

1.458 

0 

72,456 

105.577 

THE    CONTROL   OF    FLOODS    BY    RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

ONAL  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  12,  page  158.) 


371 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000  acre 

-feet  capacity 

Flood 

cortrol 

Passed 

water 

Seasonally 
stored 
water  in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 

ove  r 

spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

by  dam 
for  prior 

rights 
(*irst  152 
second- 
feet  of 
natural 
flow)  in 
acre-feet 

passing 
-Azusa 
during 
flood 
season 
at  ratee 
less  than 

1,900 
second- 
feet  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Year  and 
month 

1912 

0 

0 

0 

0 

2,710 

0 

0 

0 

0 

Jan. 

0 

0 

0 

0 

2,2.30 

0 

0 

0 

0 

Feb. 

0 

0 

0 

0 

8,199 

0 

0 

0 

0 

Mar. 

2,.314 

95 

0 

14,701 

8,515 

0 

2.314 

95 

0 

April 

4,273 

163 

0 

21,777 

8.828 

0 

4,273 

163 

0 

May 

4,634 

182 

0 

19,413 

4,990 

0 

4,634 

182 

0 

June 

4,790 

184 

0 

14,597 

3,060 

0 

4,790 

184 

0 

July 

4,790 

1.35 

0 

9,623 

1,960 

0 

4.790 

135 

0 

Aug. 

4,634 

64 

0 

4,698 

1,550 

0 

4,634 

64 

0 

Sept. 

0 

0 

0 

0 

1,830 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

1,730 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

1,760 

0 

0 

0 

0 

Dec. 
Total  or 
average 

25,435 

823 

0 

47,362 

0 

25,435 

823 

0 

1913 

0 

0 

0 

0 

2,910 

0 

0 

0 

0 

Jan. 

0 

0 

0 

0 

4,753 

0 

0 

0 

0 

Feb. 

0 

0 

0 

8,447 

8,759 

0 

0 

0 

0 

Mar. 

1,.547 

75 

0 

9,888 

7,091 

0 

1,547 

75 

0 

.April 

1,608 

93 

0 

8,315 

4,970 

0 

1,608 

93 

0 

May 

1,557 

95 

0 

6,614 

2,890 

0 

1,557 

95 

0 

June 

1,607 

93 

0 

4,962 

1,690 

0 

1,607 

93 

0 

July 

1,607 

68 

0 

3,262 

1,070 

0 

1,607 

68 

0 

Aug. 

1,555 

32 

0 

1,587 

893 

0 

1,555 

32 

0 

Sept. 

0 

0 

0 

0 

910 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

2,280 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

2,170 

0 

0 

0 

0 

Dec. 
Total  or 
average 

9,481 

456 

0 

40,386 

0 

9,481 

456 

0 

1914 

0 

0 

0 

0 

6,271 

0 

0 

0 

0 

Jan. 

0 

0 

0 

.55,129 

8,440 

18,017 

0 

0 

0 

Feb. 

0 

0 

0 

149,672 

9,.344 

30,254 

0 

0 

0 

Mar. 

16,225 

298 

0 

158,074 

9,042 

0 

2.5,519 

405 

0 

April 

19,239 

391 

0 

144,508 

9,344 

0 

28,847 

514 

0 

May 

20,460 

430 

0 

122,703 

8,585 

0 

29,763 

.549 

0 

June 

21,473 

430 

0 

93,386 

5,570 

0 

31,083 

543 

0 

July 

21,473 

313 

0 

61,700 

3,6.30 

0 

31,083 

389 

0 

-Aug. 

20,780 

165 

{) 

30,288 

2,730 

0 

30,088 

200 

0 

Sept. 

0 

0 

0 

0 

2,770 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

2,440 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

4,290 

0 

0 

0 

0 

Dec. 
Total  or 
average 

119,650 

2,027 

0 

72,456 

4S.27I 

176,383 

2,600 

0 

.'{72  WATER   R?:SOUKCES   OF    CALIFORNIA. 

TABLE   12a  (Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL  AND  SEAS 

Monthly  Summary  of  Compute 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  con 

trol  reserve  or  first 

ia 

131,000  acre-feet  of  capacity 

lOVfUW  tttlC- 

Flood 

Flood 

control 

control 

Run-off 

at 
.\zusa 

Passed 

water 

Passed 

water 

Year  and 
month 

Stage  of 
rcser\oir 

by  dam 

for  prior 

rights 

pissing 
.\zusa 
d.iring 

Seasonally 

Evapora- 
tion 

Waste 

Stage  of 
reservoir 

by  dam 

for  prior 

rischts 

passing 
.\zusa 
during 

in 

at 
beginning 

(&Tst  152 

flood 

stored 

trom 

over 

at 

(first  1.52 

flood 

acre-feet 

second- 

season 

water  in 

reservoir 
surface 

in 
acre-feet 

spillway 

beginning 

second- 

season 

01 

month  in 
acre-feet 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1,900 

acre-feet 

in 
acre-feet 

of 
month  in 
acre-feet 

feet  of 
natural 
flaw)  in 

at  rates 

loss  than 

1.900 

acre-feet 

second- 
feet  in 
acre-feet 

acre-feet 

second- 
feet  in 
acre-fee t 

1915 

.Ian. 

7,380 

0 

4,428 

2,632 

0 

0 

0 

0 

4,428 

0 

Feb. 

30,200 

320 

8,412 

13,196 

0 

0 

0 

2,952 

8,412 

0 

Mar. 

2 1, .'500 

8,912 

9,344 

0 

0 

0 

0 

24.740 

9,344 

0 

April 

17,300 

21,068 

9,042 

0 

3,.339 

117 

0 

36.896 

9,042 

0 

May 

20,400 

25.870 

9,344 

0 

4.2.56 

177 

0 

39,109 

9,.344 

0 

Jump 

11,400 

32,403 

8,967 

0 

7.807 

238 

0 

42.213 

8,967 

0 

.bily 

7,010 

26,881 

7,010 

0 

8,875 

254 

0 

34,2J1 

7.010 

0 

Aug. 

3,980 

r<,752 

3,980 

0 

8,875 

190 

0 

22,595 

3,980 

0 

Sept. 

3,270 

8,687 

3,270 

0 

8,502 

95 

0 

11,062 

3,270 

0 

Oct. 

2,770 

0 

2,770 

0 

0 

0 

0 

0 

2.770 

0 

Nov. 

3,010 

0 

3,010 

0 

0 

0 

0 

0 

3,010 

(1 

Dec. 

3,580 

0 

3,580 

0 

0 

0 

0 

0 

3,580 

0 

Total  or 
average 

131,800 

7.3,157 

15,828 

41,744 

1,071 

0 

73,1.57 

0 

1916 

.)ati. 

148,000 

0 

8,759 

52,702 

0 

0 

0 

0 

8,753 

49,196 

Feb. 

3!),400 

86,539 

8,741 

99,427 

0 

0 

0 

90,045 

8,741 

54,.508 

Mar. 

34,800 

17,771 

9,344 

18 

0 

0 

0 

66,196 

9,344 

0 

April 

10,!)00 

43,209 

9,0'.2 

0 

6,913 

174 

0 

91,6,52 

9.042 

0 

May 

10,400 

46,980 

9,130 

0 

9,304 

248 

0 

87,483 

9.130 

0 

.Func 

5,830 

38,098 

5,830 

0 

9,314 

264 

0 

70,993 

5,830 

0 

July 

4,770 

29,120 

4,770 

0 

9.624 

264 

0 

53.444 

4,770 

0 

Aug. 

3,570 

19,232 

3,570 

0 

9,621 

198 

0 

35,328 

3,570 

0 

Sept. 

2,810 

9,410 

2,810 

0 

9,314 

96 

0 

17,314 

2,810 

0 

Oct. 

(,0!0 

0 

6,473 

0 

0 

0 

0 

0 

6,473 

0 

Nov. 

4,130 

537 

4,130 

0 

0 

7 

0 

537 

4.130 

0 

Dec. 

13,600 

.530 

5,253 

0 

0 

0 

0 

530 

5,253 

0 

Total  or 
average 

294,220 

77,852 

152,147 

54.093 

1,251 

0 

77,852 

103.701 

1917 

Jan. 

9.280 

8.877 

8,172 

9,467 

0 

0 

0 

8,877 

8,172 

0 

Feb. 

13.200 

518 

7,.551 

0 

0 

0 

0 

9.985 

7.,551 

0 

Mar. 

13,600 

6,167 

9„344 

0 

0 

0 

0 

15,634 

i',344 

0 

April 
May 

tC.'iOO 

10,423 

9,042 

0 

I,G40 

73 

0 

19,890 

9.042 

0 

8,610 

10.168 

8„531 

0 

1,979 

99 

0 

18,086 

8,531 

0 

June 

5,270 

8,169 

5,270 

0 

1,935 

105 

0 

14,482 

5,270 

0 

July 

3,140 

6,129 

3,140 

0 

1,999 

99 

(1 

10,882 

3,140 

0 

Aug. 

2,200 

4,031 

2,200 

0 

1,999 

67 

0 

7,169 

2,200 

0 

Sept. 

1,510 

1,965 

1,510 

0 

1,935 

30 

0 

3,497 

1,510 

0 

Oct. 

1.560 

0 

1,560 

0 

0 

0 

0 

0 

1,560 

0 

Nov. 

1.840 

0 

1,840 

0 

0 

0 

0 

0 

1,840 

(I 

Dec. 
Tutnl  or 

2,000 

0 

2,000 

0 

o| 

0 

0 

0 

2,000 

0 

average 

72.710 
1 

60.160 

9.467| 

11.487 

473 

0 

60,160 

(} 

THE    fONTROL   OF    FLOODS    BY    RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

ONAL  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  12,  page  158.) 


373 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000  acre- 

feet  capacity 

Flood 

control 

Passed 

water 

Seasonally 

Evapora- 
tion 

Waste 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

by  dam 

for  prior 

rights 

passing 
Arusa 
during 

Seasonally 

Evapora- 
tion 

Waste 

Year  and 
month 

stored 
WMterin 
acre-feet 

from 
reservoir 
surface 

in 
acre-feet 

over 

spillway 

in 

acre-feet 

(first  152 
second- 
feet  of 
natural 
flow)  in 

flood 

season 

at  rates 

less  than 

1,900 

stored 
water  in 
acre-feet 

from 
reservoir 
surface 

in 
acre-feet 

over 
spillway 

in 
acre-feet 

acre-feet 

second- 
feet  in 

>> 

acre-feet 

1915 

0 

0 

0 

0 

4,428 

0 

0 

0 

0 

Jan. 

0 

0 

0 

2,952 

8,412 

0 

0 

0 

0 

Feb. 

0 

0 

0 

24,740 

9,344 

0 

0 

0 

0 

Mar. 

5,88» 

101 

0 

36,896 

9,042 

0 

5,884 

161 

0 

April 

7,728 

224 

0 

39,109 

9,344 

0 

7,728 

224 

0 

May 

10,165 

280 

0 

42,213 

8,967 

0 

10,165 

280 

0 

June 

11,313 

293 

0 

34,201 

7,010 

0 

11,313 

293 

0 

July 

11,313 

220 

0 

22,595 

3,980 

0 

11,313 

220 

0 

Aug. 

10,947 

115 

0 

11,062 

3,2;  0 

0 

10,947 

115 

0 

Sept. 

0 

0 

0 

0 

2,770 

0 

0 

0 

0 

f)et. 

0 

0 

0 

0 

3,010 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

3,580 

0 

0 

0 

0 

Dec. 
Total  or 
average 

57,300 

1,293 

0 

73,157 

0 

57,350 

1,293 

0 

1916 

0 

0 

0 

0 

8,759 

0 

0 

0 

0 

Jan. 

0 

0 

0 

139,241 

8,741 

43,704 

0 

0 

0 

Feb. 

0 

0 

0 

126,196 

9,344 

0 

0 

0 

0 

Mar. 

14,747 

280 

0 

151,652 

9,042 

0 

24,473 

393 

0 

April 

17,393 

307 

0 

137,644 

9,130 

0 

27,472 

496 

0 

May 

17,165 

384 

0 

110,946 

5,830 

0 

26,895 

513 

0 

June 

17,736 

380 

0 

83,538 

4,770 

0 

27,793 

498 

0 

July 

17,736 

278 

0 

5.5,247 

3,570 

0 

27,793 

363 

0 

Aug. 

17,168 

146 

0 

27,091 

2,810 

.     0 

26,904 

187 

0 

Sept. 

0 

0 

0 

0 

6.473 

1) 

0 

0 

0 

Oct. 

0 

7 

0 

,537 

4,130 

0 

0 

7 

0 

Nov. 

0 

0 

0 

530 

5,253 

0 

0 

0 

0 

Dec. 
Total  or 
average 

101,945 

1,842 

0 

77,852 

43,704 

161,330 

2,457 

0 

1917 

0 

0 

0 

8,877 

8,172 

0 

0 

0 

0 

Jan. 

0 

0 

0 

9,985 

7,551 

0 

0 

0 

0 

Feb. 

0 

0 

0 

15,634 

9,344 

0 

0 

0 

0 

Mar. 

3,149 

113 

0 

19,890 

9,042 

0 

3,149 

113 

0 

April 

3,536 

147 

0 

18,086 

8,5ol 

0 

3,536 

147 

0 

May 

3,446 

154 

0 

14,482 

.5,270 

0 

3,446 

154 

0 

J>me 

3,501 

152 

0 

10,882 

3,140 

0 

3,501 

152 

0 

July 

3,561 

111 

0 

7,169 

2,200 

0 

3,561 

111 

0 

Aug. 

3,445 

52 

0 

3,497 

1,510 

0 

3,445 

52 

0 

Sept 

0 

0 

0 

0 

1,560 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

1,840 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

2,000 

0 

0 

0 

0 

Dec. 

Total  or 
average 

20,698 

729 

0 

00,160 

0 

20,698 

729 

t 

374  WATER    RESOURCES   OF    CALIFORNIA. 

TABLE  12a  (Continued).     SAN  GABRIEL 
WATER  YIELD  UNDER 

FLOOD  CONTROL  AND  SEAS 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  control  reserve  or  first 
131,000  acre-feet  of  capacity 

180,000  acre- 

Flood 

Flood 

control 

control 

Passed 

water 

Passed 

water 

Year  and 
month 

Run-off 

at 
Azusa 

Stage  of 
reservoir 

by  dam 

for  prior 

rights 

passing 
Azusa 
during 

Seasonally 

Evapora- 
tion 
fiom 
reservoir 
surface 

in 
acre-feet 

Waste 

Stage  of 
reservoir 

by  dam 

for  prior 

rights 

pissing 
.\zusa 
during 

in 
acre-feet 

ai 
beginning 

(first  152 
second- 

flood 
season 

?  to  red 
water  in 

over 
spillway 

at 
beginning 

of 
month  in 
acre-feet 

(first  152 
second- 

flood 
season 

of 
month  in 
acre-feet 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1,900 

acre-feet 

in 
acre-feet 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1.900 

acre-feet 

second- 
feet  in 
acre-feet 

acre-feet 

second- 
feet  in 
acre-feet 

1918 

Jan. 

2,020 

0 

2,020 

0 

0 

0 

0 

0 

2.020 

0 

Feb. 

9,330 

0 

3,817 

0 

0 

0 

0 

0 

3.847 

0 

Mar. 

73,200 

5,t83 

9,249 

11, .341 

0 

0 

0 

5,483 

9.249 

0 

April 

IV, 000 

58,093 

9,012 

0 

9,314 

206 

0 

69,434 

9.042 

0 

May 

10.000 

56,531 

8.993 

0 

11,216 

276 

0 

66.012 

8.993 

0 

June 

6,010 

46,016 

6,010 

0 

11.097 

292 

0 

53,603 

6,010 

0 

July 

3,970 

34.657 

3,970 

0 

11,467 

293 

0 

40..347 

3.970 

0 

Aug. 

2,840 

22,8ii7 

2,840 

0 

11.467 

218 

0 

26.663 

2.840 

0 

Sept. 

2,330 

11.212 

2.330 

0 

11,099 

113 

0 

13,060 

2.330 

0 

Oct. 

2.930 

0 

2  930 

0 

0 

0 

0 

0 

2,930 

0 

Nov. 

3,140 

0 

3,140 

0 

0 

0 

0 

0 

3,140 

0 

Dec. 
Total  or 
average 

4,370 

0 

4,370 

C 

0 

0 

0 

0 

4,370 

0 

137,110 

58,741 

11,341 

65.660 

1,398 

0 

58,741 

0 

1919 

Jan. 

3,300 

0 

3,300 

0 

0 

0 

0 

0 

3.300 

0 

Feb. 

^110 

0 

4  110 

0 

0 

0 

0 

0 

4,110 

0 

Mar. 

6,110 

0 

6,110 

0 

0 

0 

0 

0 

6,110 

0 

April 
May 

6,010 

0 

6,010 

0 

0 

0 

0 

0 

6,010 

0 

3,810 

0 

3.810 

0 

0 

0 

0 

0 

3,810 

0 

June 

1,890 

0 

1 ,890 

0 

0 

0 

0 

0 

1,890 

0 

July 

1.320 

0 

1,320 

0 

0 

0 

0 

0 

1,320 

0 

Aug. 

935 

(1 

935 

0 

0 

0 

0 

0 

935 

0 

Sept. 

1,010 

0 

1,010 

•  c 

0 

0 

0 

0 

1.010 

0 

Oct. 

2.040 

0 

2,040 

0 

0 

0 

0 

0 

2,040 

0 

Nov. 

2,130 

0 

2,130 

0 

0 

0 

0 

0 

2,130 

0 

Dec. 
Total  or 
average 

5.340 

0 

5,209 

0 

0 

0 

0 

0 

5,209 

0 

38,005 

37,874 

0 

0 

0 

0 

37,874 

0 

1920 

Jan. 

3,260 

131 

3,260 

0 

0 

0 

0 

131 

3,260 

0 

Feb. 

12.700 

131 

5.854 

0 

0 

0 

0 

131 

5.851 

0 

Mar. 

36,200 

6.977 

9.344 

0 

0 

0 

0 

6.977 

9.344 

0 

April 
May 

25.100 

33.833 

9.042 

0 

5,389 

153 

0 

33,833 

9,0^2 

0 

12.600 

44.349 

9,344 

0 

8,776 

240 

0 

44,.349 

9.344 

June 

7.380 

38. ,589 

7,349 

0 

9,286 

264 

0 

38.589 

7,3-(9 

July 

4.670 

29.070 

4,670 

0 

9,603 

270 

0 

29,070 

4,670 

Aug. 

3,200 

19,197 

3.2C0 

0 

9,603 

200 

0 

19.197 

3.200 

Sept. 

2.030 

9,394 

2,0.30 

0 

9,292 

102 

0 

9.394 

2.030 

Oct. 

2,000 

0 

2,000 

0 

0 

0 

0 

0 

2,000 

0 

Nov. 

2,380 

0 

2,380 

0 

0 

0 

0 

0 

2.380 

0 

Dec. 
Total  or 
average 

2,210 

0 

2.210 

0 

0 

0 

0 

0 

2,210 

0 

113.730 

60.683 

0 

51. 949 

1,229 

0 

60,683 

0 

THE   CONTROL   OF    FLOODS   BY    RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

ONAL  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  12,  page  158.) 


375 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  capacity 

240,000  acre-feet  capacity 

Flood 

control 

Passed 

water 

Seasonally 

Evapora- 
tion 
from 

Waste 

Stage  of 
res£n.-oir 

by  dam 

for  prior 

rights 

passing 
Azusa 
during 

Seasonally 

Evapora- 
tion 

Waste 

Year  and 
month 

stored 

over 
spillway 

in 
aore-feet 

at 

(first  152 

flood 

Stored 

trom 

over 
spillway 

in 
acre-feet 

water  in 
acre-feet 

reser\-oir 
surface 

in 
acre-feet 

besinnin^ 

of     ■ 

month  in 

acre-feet 

second- 
feet  of 
natural 
flow)  in 

season 

at  rates 

less  than 

1,900 

water  in 
acre-feet 

reservoir 
surface 

in 
acre-feet 

acre-feet 

second- 
feet  in 
acre-feet 

1918 

0 

0 

0 

0 

2,020 

0 

0 

0 

0 

Jan. 

0 

0 

0 

0 

3,847 

0 

0 

0 

0 

Feb. 

0 

0 

0 

5,483 

9.249 

0 

0 

0 

0 

Mar. 

11,146 

234 

0 

69.434 

9,042 

0 

11,146 

2.34 

0 

.^pril 

13,110 

306 

0 

66,012 

8,993 

0 

13,110 

306 

0 

May 

12.933 

323 

0 

53.603 

6.010 

0 

12,933 

323 

0 

June 

13,363 

321 

0 

40,347 

3,970 

0 

13,363 

321 

0 

July 

13,363 

240 

C 

26,663 

2,840 

0 

13,363 

240 

0 

Aug. 

12,933 

127 

0 

13,060 

2,330 

0 

12,933 

127 

0 

Sept. 

0 

0 

0 

0 

2.930 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

3,140 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

4,370 

0 

0 

0 

0 

Dec. 
Total  or 
average 

76,818 

1,551 

0 

58.741 

0 

76,848 

1,551 

0 

1919 

0 

0 

0 

0 

3,300 

0 

0 

0 

0 

Jan. 

0 

0 

0 

0 

4,110 

0 

0 

0 

0 

Feb. 

0 

0 

0 

0 

6,110 

0 

0 

0 

0 

Mar. 

0 

0 

0 

0 

6,010 

0 

0 

0 

0 

.\pril 

0 

0 

0 

0 

3,810 

0 

0 

0 

0 

May 

0 

0 

0 

0 

1,890 

0 

0 

0 

0 

June 

0 

0 

0 

0 

1.320 

0 

0 

0 

0 

July 

0 

0 

0 

0 

935 

0 

0 

0 

0 

.\ug. 

0 

0 

0 

0 

1,010 

0 

0 

0 

0 

Sept. 

0 

0 

0 

0 

2,040 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

2,130 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

5,209 

0 

0 

0 

0 

Dec. 

Total  or 
average 

0 

0 

0 

37,874 

0 

0 

0 

0 

1920 

0 

0 

0 

131 

3,260 

0 

0 

0 

0 

Jan. 

0 

0 

0 

131 

5,854 

0 

0 

0 

0 

Feb. 

0 

0 

0 

6,977 

9.344 

0 

0 

0 

0 

Mar. 

5.389 

153 

0 

33,833 

9.042 

0 

5,.389 

153 

0 

April 

8.776 

240 

0 

44,349 

9..344 

0 

8,776 

240 

0 

May 

9,286 

264 

0 

38,589 

7,349 

0 

9,286 

264 

0 

June 

9,603 

270 

0 

29,070 

4.670 

0 

9.603 

270 

0 

July 

9,603 

200 

0 

19,197 

3,200 

0 

9,603 

200 

0 

.\ug. 

9,292 

102 

0 

9,394 

2,030 

0 

9,292 

102 

0 

Sept. 

0 

0 

0 

0 

2,000 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

2,380 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

2,210 

0 

0 

0 

0 

Dec. 

Total  or 
average 

51,949 

1,229 

0 

60,683 

0 

51,949 

1,229 

0 

:}7<)  WATER  RESOURCES  OF    CALIFORNIA. 

TABLE  12a  (Continued;.     SAN  GABRIEL 
WATER  YIELD  UNDER 

FLOOD  CONTROL  AND  SEAS 
Monthly  Summary  of  Compute 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flootJ  ccn 

trol  reserve  or  first 

1B 

r\  nnn  ««*»_ 

131,000  acre-feet  of  capacity 

1  OxifViju   ai.1  c- 

Flood 

Flood 

control 

control 

Hun-aff 
at 

Passed 

water 

Passed 

water 

Year  and 

Staec  of 

by  dam 
for  prior 

passing 
Azusa 

Evapora- 

Waste 

Stage  of 

by  dam 
for  prior 

passing 
Azusa 

month 

.^zu.sa 

reservoir 

rights 

during 

Seasonally 

tion 

reservoir 

rights 

during 

in 

at 

(first  152 

flood 

stored 

from 

i)\  er 
spillway 

at 

(first  152 

flood 

acre-fee t 

beginning 

second- 

season 

water  in 

reservoir 
surface 

beginning 

second- 

season 

of 

!eet  of 

at  rates 

acre-feet 

m 
acre-feet 

01 

month  in 
acre-feet 

feet  of 

atiate? 

month  in 
acre-fee' 

natural 
flow)  in 

less  than 
1,900 

in 
acre-feet 

natural 
flow)  in 

less  than 
1,900 

acre-feet 

second- 
feet  in 
acre-feet 

acre-feet 

second- 
feet  in 
acre-feet 

1921 

Jan. 

5.100 

0 

4,405 

0 

0 

0 

0 

0 

4,405 

0 

Feb. 

4,490 

755 

4,490 

0 

0 

0 

0 

755 

4,490 

0 

Mar. 

15,400 

755 

7,288 

0 

0 

0 

0 

755 

7,288 

0 

April 

6,070 

8,867 

6,070 

0 

1,386 

67 

0 

8,837 

6,070 

0 

May 

15,700 

7,414 

6.835 

0 

1,432 

85 

0 

7,414 

6,835 

0 

Juno 

8,980 

14,762 

7,(i2j 

0 

3,510 

1.55 

0 

14,762 

7,920 

0 

July 

3,830 

12,157 

3,830 

0 

3,978 

169 

0 

12,157 

3,830 

0 

Aug. 

2,450 

8.010 

2,450 

0 

3,978 

121 

0 

8,010 

2,450 

0 

Sept. 

1,840 

3,911 

1,840 

0 

3,859 

52 

0 

3,911 

1,840 

0 

Oct. 

2,040 

0 

2,040 

0 

0 

0 

0 

0 

2,040 

0 

Nov. 

1,800 

0 

1,800 

0 

0 

0 

0 

0 

1,800 

0 

Dec. 
Total  or 
average 

119,000 

0 

5,045 

38,907 

0 

0 

0 

0 

5,045 

6,295 

186,760 

54,013 

38,907 

18,143 

649 

0 

54,013 

6,295 

1922 

Jan. 

62,100 

75.048 

9,344 

108.425 

0 

0 

0 

107,660 

9,344 

100,784 

I'Vl). 

88,900 

19,379 

8,440 

83,060 

0 

0 

0 

59,632 

8,440 

74,313 

Mar. 

47,800 

16,779 

9.344 

3,196 

0 

0 

0 

65,779 

9,344 

3,353 

Auril 
May 

31,400 

52,039 

9,042 

0 

8,334 

192 

0 

100.882 

9,012 

0 

24,700 

65,871 

9,344 

0 

13,084 

303 

0 

106,702 

9,344 

0 

June 

14,400 

67,840 

9,012 

0 

16,400 

373 

0 

100,363 

9,012 

0 

July 

9,100 

56,425 

8,576 

0 

18,735 

392 

0 

80,924 

8,576 

0 

Auk. 

5.080 

37.822 

5,080 

0 

18,997 

287 

0 

54,037 

5,080 

0 

Sept. 

3,290 

18,538 

3,290 

0 

18,385 

153 

0 

26,493 

3,290 

0 

Oct. 

3,110 

0 

3,110 

0 

0 

0 

0 

0 

3,110 

0 

Nov. 

5,310 

0 

4,519 

0 

0 

0 

0 

0 

4,519 

0 

Dec. 
Total  or 
average 

21,500 

791 

8,466 

0 

0 

0 

0 

791 

8,456 

0 

316,690 

87,587 

194,681 

93,935 

1,700 

0 

87,587 

178,4.50 

1923 

Jan. 

7.130 

13,835 

6,968 

13,042 

0 

0 

0 

13,835 

6,968 

0 

Feb. 

7,830 

955 

7,791 

0 

0 

0 

0 

13,997 

7  791 

0 

Mar. 

7,320 

994 

7,320 

0 

0 

0 

0 

14,036 

7,320 

0 

April 
May 

8,330 

994 

8,079 

0 

157 

8 

0 

14,036 

8,079 

0 

5,480 

1.080 

5,480 

0 

210 

12 

0 

11,983 

5,480 

0 

June 

3,700 

858 

3,700 

0 

2W 

12 

0 

9.537 

3,700 

0 

July 

2,420 

t>42 

2,420 

0 

212 

8 

0 

7,159 

2,420 

0 

Auk. 

1,990 

422 

1.990 

0 

212 

6 

0 

4,707 

1,990 

0 

Sept. 

1.750 

204 

1,7.50 

0 

204 

0 

0 

2,293 

1.750 

0 

Oct. 

1.71(1 

0 

1,710 

0 

0 

0 

0 

0 

1,710 

0 

Nov. 

1 ,960 

(1 

1.960 

0 

0 

0 

0 

0 

1,960 

0 

Der. 
Total  or 
averiiKO 

2,130 

0 

2.130 

0 

0 

0 

0 

0 

2,130 

(1 

61.760 

51,298 

13,042 

1,199 

46 

0 

61.298 

(1 

THE    CONTROL    OF    FLOODS    BY    RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

ONAL  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  12,  page  158.) 


377 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000  acre 

-feet  capacity 

Flood 

control 

Passed 

water 

Seasonally 
stored 

Evapora- 
tion 
from 

Waste 
over 

Stage  of 

reser\oir 

at 

by  dam 
for  prior 

rights 
(first  152 

pissing 
Azusa 
during 
flood 

Seasonally 
stored 

Evai)ora- 
tion 
from 

Waste 

over 

spillway 

Year  and 
month 

water  in 

reservoir 
surface 

in 
acre-feet 

spillway 

beginning 

second- 

season 

water  in 

reservoir 
surface 

in 
acre-feet 

acre-feet 

in 
acre-feet 

of 
month  in 
acre-feet 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1,900 

acre-feet 

in 
acre-feet 

acre-feet 

second- 
feet  in 
acre-feet 

1921 

0 

0 

0 

0 

4,405 

0 

0 

0 

0 

Jan. 

0 

0 

0 

755 

4.490 

0 

0 

0 

0 

Feb. 

0 

0 

0 

755 

7,288 

0 

0 

0 

0 

Mar. 

1,386 

67 

0 

8,867 

6,070 

0 

1,386 

67 

0 

April 

1,432 

85 

0 

7,414 

6,835 

0 

1,432 

85 

0 

May 

3,510 

155 

0 

14,762 

7,920 

0 

3,510 

155 

0 

June 

3,978 

169 

0 

12,157 

3,830 

0 

3,978 

169 

0 

July 

3,978 

121 

0 

8,010 

2,450 

0 

3,978 

121 

0 

Aug. 

3,859 

52 

0 

3,911 

1,840 

0 

3,859 

52 

0 

Sept. 

0 

0 

0 

0 

2,040 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

1,800 

0 

0 

0 

0 

Nov. 

0 

0 

0 

0 

5.045 

0 

0 

0 

0 

Dec. 
Total  or 
average 

18,143 

649 

0 

54  013 

0 

18,143 

649 

0 

1922 

0 

0 

0 

113,955 

9, ,344 

52,703 

0 

0 

0 

Jan. 

0 

0 

0 

114,008 

8,440 

68,689 

0 

0 

0 

Feb. 

0 

0 

0 

125,779 

9,344 

3,196 

0 

0 

0 

Mar. 

lfi,241 

297 

0 

161,039 

9,042 

0 

25,999 

411 

0 

April 

21,277 

418 

0 

156,987 

9,344 

0 

31,353 

515 

0 

May 

24,317 

480 

0 

140,445 

9,042 

0 

34,086 

603 

0 

June 

26,917 

494 

0 

111.114 

8,576 

0 

37,012 

611 

0 

July 

27,185 

359 

0 

74,015 

5,080 

0 

37,280 

434 

0 

Aug. 

26,306 

187 

0 

36,301 

3,290 

0 

36,081 

220 

0 

Sept. 

0 

0 

0 

0 

3,110 

0 

0 

0 

0 

Oct. 

0 

0 

0 

0 

4,519 

0 

0 

0 

0 

Nov. 

0 

0 

0 

791 

8,456 

0 

0 

0 

0 

Dec. 

142,243 

2,235 

0 

87,.587 

124.588 

201,811 

2,824 

0 

1  \jliii  \ii 

average 
1923 

0 

0 

0 

13,835 

6,968 

0 

0 

0 

0 

.Ian. 

I              0 

0 

0 

13,997 

7.791 

0 

0 

0 

0 

Feb. 

\             0 

0 

0 

14,036 

7.320 

0 

0 

0 

0 

Mar. 

2,211 

93 

0 

14,036 

8,079 

0 

2,211 

93 

0 

.April 

2,331 

115 

0 

11,983 

5.480 

0 

2,331 

115 

0 

May 

2,257 

121 

0 

9,.537 

3,700 

0 

2,257 

121 

0 

June 

2.331 

121 

0 

7,159 

2.420 

0 

2,331 

121 

0 

July 

2, .331 

83 

0 

4.707 

1.990 

0 

2.331 

83 

0 

Aug. 

2,253 

40 

0 

2.293 

1.750 

0 

2,253 

40 

0 

Sept. 

0 

0 

0 

0 

1.710 

0 

0 

0 

0 

Oct. 

n 

0 

0 

0 

1 ,960 

0 

0 

0 

0 

Nov 

0 

0 

0 

0 

2,130 

" 

0 

0 

0 

Doc. 
Total  or 

13,714 

573 

0 

51,298 

0 

13,714 

,       573 

0 

average 

24—52411 


378 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  12a  (Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL  AND  SEAS 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Run-off 

at 

Azusa 

in 

acre-feet 

Maximiim  flood  control  reserve  or  first 
131,000  acre-feet  of  capacity 

180,000  acre- 

Year  and 
month 

Stage  of 
rejervoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 

for  prior 
rights 

(first  152 
second- 
feet  of 
natural 
flow)  in 

acre-feet 

Flood 

control 
water 

passing 
Azusa 
during 
flood 
season 

at  rates 

less  than 

1,900 

second- 
feet  in 

acre-feet 

Seasonally 

stored 

water  in 

acre-feet 

Evapora- 
tion 
from 

reservoir 

surface 
in 

acre-feet 

Waste 
over 

spillway 
in 

acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 

for  prior 
rights 

(first  152 
second- 
feet  of 
natural 
flow)  in 

acre-feet 

Flood 
control 
water 
passing 
Azusa 
during 
flood 
season 
at  rates 
less  than 

1,900 
second- 
feet  in 
acre-feet 

1924 

Jan. 
Feb. 
Mar. 
April 
Ma> 
June 
July 
Aug. 
Sept. 
Ocl. 
Nov. 
Dec. 
Total  or 
average 

1925 

Jan. 
Feb. 
Mar. 
April 
May 
June 
July 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
Total  or 
average 

2,170 

1,790 

4,130 

6,190 

3,650 

1,600 

1,000 

750 

744 

873 

1,190 

1,780 

0 

0 

0 

416 

349 

278 

209 

136 

65 

0 

0 

0 

2,170 

1,790 

3,714 

6,190 

3,650 

1,660 

1,000 

756 

744 

873 

1,190 

1,780 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 

0 

0 

59 

61 

59 

61 

61 

59 

0 

0 

0 

0 
0 
0 
8 

10 
10 
12 
10 
6 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 

0 

0 

416 

349 

278 

209 

136 

65 

0 

0 

0 

2,170 

1,790 

3,714 

6,190 

3,650 

1,660 

1,000 

750 

744 

873 

1  190 

1,780 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

25,933 

1,710 

1 ,020 

2,510 

7,200 

3,050 

1,840 

82-1 

621 

492 

873 

1,010 

1,050 

0 

0 

0 

87 

1,518 

1,204 

898 

589 

288 

0 

0 

0 

25,517 

1,710 

1,620 

2.423 

5,765 

3,050 

1,840 

824 

621 

492 

873 

1,010 

1,650 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

360 

0 

0 

0 

0 

285 

278 

285 

285 

278 

0 

0 

0 

56 

0 
0 
0 
4 

29 

28 

24 

16 

10 

0 

0 

0 

0 

0 
0 
0 
0 
0 
0 
0 

u 

0 
0 
0 
0 

0 

0 

0 

87 

1.518 

1,204 

8',18 

589 

288 

0 

0 

0 

25,517 

1,710 

1,620 

2,423 

5,765 

3,050 

1,840 

824 

621 

492 

873 

1.010 

1,650 

0 
0 

0 
0 
0 
0 
0 

23,400 

21.878 

0 

1,411 

111 

0 

21,878 

0 

THE   CONTROL   OF    FLOODS   BY   RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

ONAL  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  12,  page  158.) 


379 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  capacity 

2'10,000  acre-feet  capacity 

Seasonally 
stored 
water  in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 

rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 
acre-feet 

Flood 
control 
water 
passing 
Aznsa 
during 
flood 
season 
at  rates 

less  than 

1,900 
second- 
feet  in 

acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Year  and 
•   month 

0 

0 

0 

59 

61 

59 

61 

61 

59 

0 

0 

0 

0 
0 
0 
8 
10 
10 
12 
10 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 

0 
0 
0 
0 
0 
0 

0 

I 

416 

.349 

278 

209 

136 

65 

0 

0 

0 

2,170 

1,790 

3,714 

6,190 

3,650 

1,660 

1,000 

756 

744 

873 

1,190 

1,780 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

0 

0 

0 

59 

61 

59 

61 

61 

59 

0 

0 

0 

0 
0 
0 
8 

10 
10 
12 
10 
6 
0 
0 
0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

1924 

Jan. 
Feb. 
Mar. 
April 
May 
June 
July 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
Total  or 
average 

1925 

Jan. 
Feb. 
Mar. 
April 
May 
June 
July 
Aug. 
Sept. 
Oct. 
Nov. 
Dec. 
Total  or 
average 

360 

0 

0 

0 

0 

285 

278 

285 

L          285 

t         278 

W             0 

0 

0 

56 

0 

0 

0 

4 

29 

28 

24 

16 

10 

0 

0 

0 

0 

0 
0 
0 

u 
<l 
(1 

0 
0 
0 
0 
0 
0 

0 

0 

0 

87 

1,518 

1,204 

898 

589 

288 

0 

0 

0 

25,517 

1,710 

1,620 

2,423 

5,765 

3,050 

1,840 

824 

621 

492 

873 

1,010 

1,650 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

360 

0 

0 

0 

0 

285 

278 

285 

285 

278 

0 

0 

0 

56 

0 
0 
0 
4 

29 

28 

24 

16 

10 

0 

0 

0 

0 

0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 

1,411 

111 

0 

21,878 

0 

1,411 

111 

0 

380 


WATER   RESOURCES  OF    CALIFORNIA. 


TABLE  12a  (Concluded).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL  AND  SEAS 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  control  reserve  or  first 
131,000  acre-feet  of  capacity 

180,000  acre- 

Flood 

Flood 

control 

control 

Run-ofT 

at 
Azusa 

Passed 

witer 

Passed 

water 

Year  and 
month 

Stage  of 
re  iervoir 

by  dam 

for  prior 

rights 

passing 
Azusa 
during 

S3.isonally 

Evapora- 
tion 

Waste 

Stage  of 
reservoir 

at 
beginning 

of 

by  dam 

for  prior 

rights 

passing 
Azuaa 
during 

in 
acre-feet 

at 
beginning 

of 
month  in 
acre-feet 

(first  152 
second- 

flood 
season 

stored 
water  in 

irom 
reservoir 
surface 

in 
acre-feet 

over 
spillway 

(first  152 
second- 

flood 
season 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1,900 

acre-feet 

in 
acre-feet 

month  in 
acre-feet 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1,900 

acre-feet 

second- 
feet  in 
acre-feet 

acre-feet 

second- 
feet  in 
acre-feet 

192' 

,!an. 

\Mi) 

0 

1.540 

0 

0 

0 

0 

0 

1,540 

0 

Feb. 

7,1140 

0 

5,485 

0 

0 

0 

0 

0 

5,485 

0 

Mar. 

3.fi50 

2,455 

3,650 

0 

0 

0 

0 

2,455 

3,650 

0 

April 

69,000 

2,455 

8,233 

0 

383 

32 

0 

2,455 

8,233 

0 

May 

13,000 

62,807 

9,142 

0 

12,471 

294 

0 

62.807 

9,142 

0 

June 

5,500 

53.900 

5,500 

0 

13.006 

323 

0 

53,900 

5.500 

0 

July 

3.120 

40,571 

3,120 

0 

13,441 

321 

0 

40,571 

3,120 

0 

Aug. 

2.070 

26.809 

2,070 

0 

13,441 

239 

0 

26,809 

2,070 

0 

Sept. 

1,.580 

13,129 

1,580 

0 

13,001 

128 

0 

13,129 

1,580 

0 

Oct. 

0 

0 

Nov. 

Dec. 
Total  or 
averagn 

107,400 

40,320 

0 

65,743 

1,337 

0 

40,320 

0 

Total  for 

period, 

Jan.1, 

1897.  to 

Ocf.1. 

1926 

3,731,977 

1,513,303 

1,103,359 

1,091,252 

24,063 

0 

1,513,303 

586,916 

Average 

for 

period. 

Jan.1, 

1897,  to 
Oct.1, 
1928 

125,445 

50,867 

37,088 

36,681 

809 

0 

50,867 

19,723 

THE    CONTROL   OF    FLOODa    BY    RESERVOIRS. 


381 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

ONAL  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  12,  page  158.) 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000  acre-feet  capacity 

Flood 

control 

Passed 

water 

Seasonally 
stored 
water  in 
aore-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 
spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

by  dam 
for  prior 

rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 
acre-feet 

passing 
Azusa 
during 
flood 
season 
at  rates 

less  than 

1,900 
second- 
feet  in 

acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Year  and 
month 

1926 

0 

0 

0 

0 

1,,540 

0 

0 

0 

0 

,Tan. 

0 

0 

0 

0 

5,485 

0 

0 

0 

0 

Feb. 

0 

0 

0 

2,455 

3.650 

0 

0 

0 

0 

Mar. 

383 

32 

0 

2,455 

8,233 

0 

383 

32 

0 

April 

12,471 

294 

0 

62.807 

9.142 

0 

12.471 

294 

0 

May 

13.006 

323 

0 

53.900 

5,.500 

0 

13,006 

323 

0 

June 

n,441 

321 

0 

40,571 

3,120 

0 

13,441 

321 

0 

July 

13,441 

239 

0 

26,809 

2.070 

0 

13,441 

2.39 

0 

Aug. 

13,001 

128 

0 

13,129 
0 

1..580 

0 

13,001 

128 

0 

Sept. 
Oct. 
Nov. 
Dec. 

Tots  lor 
average 

65,743 

1,337 

0 

40,320 

0 

65.743 

1,337 

0 

Total  for 

period, 

Jan.1, 

1897,  to 

Oct.  1  , 

1,600.181 

31,577 

0 

1,513.303 

247,712 

1,936,001 

34,961 

0 

1926 

Average 

for 

period, 

Jan.1, 

1897,  to 

Oct.1, 

53.788 

1.061 

0 

50,867 

8.327 

65,076 

1,175 

0 

1926 

382 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  13a.     SAN  GABRIEL  RESER 

WATER  YIELD  UNDER 

FLOOD  CONTROL,  SEASONAL  AND 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  ccnfrol  reserve  cr  first 

180,000  acre- 

131,000  acre-feet  of  capacity 

Flood 

Yield 

Flood 

control 

control 

Year  and 
month 

Rur-off 
at 

AZMBS. 

in 
acre  feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights 
tfirst  152 
second- 
feet  of 

water 
passing 
Azupa 
during 

flood 
season 
at  rates 

Season- 
ally 
stored 
water  in 
acre-feet 

in  a 

uni- 
formly 

con- 
tinuous 
Sjpply 

from 

Evapora- 
tion 
from 
reservoir 
surface 

Waste 
over 
ppill- 
way 
in 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights 
ffirst  152 
eecond- 
feet  of 

water 
passing 
Azusa 
during 
flood 
season 
at  rates 

natural 
flow)  in 

.ess  than 
1,900 

over- 
year 
storage 

in 
acre-feet 

acre-feet 

natural 
flow)  in 

less  than 
1.900 

acre-feet 

second- 

acre-feet 

second - 

feet  in 

in 
acre-feet 

feet  in 

acre-feet 

acre-feet 

1897 

Jan. 

3,617 

0 

3,617 

0 

0 

0 

0 

0 

62,650 

3.617 

11,779 

Feb. 

19,146 

0 

7,262 

4,913 

0 

0 

0 

0 

49,519 

7,262 

4,628 

Mar. 

28,623 

6,971 

9,344 

0 

0 

0 

0 

0 

55,553 

9,344 

0 

April 

17,519 

26,250 

9,042 

0 

4.164 

0 

131 

0 

73,480 

9,042 

0 

May 

8,851 

30,432 

8,126 

0 

5,963 

0 

194 

0 

79,165 

8.126 

0 

.lune 

4,033 

25,000 

4,033 

0 

5,985 

0 

206 

0 

75,183 

4,033 

0 

July 

2,343 

18,809 

2,343 

0 

6,185 

0 

212 

0 

70,385 

2,343 

0 

Ajg. 

1,613 

12.412 

1,613 

0 

6,185 

0 

149 

0 

65,389 

1,613 

0 

Sept. 

1,226 

6,078 

1,226 

0 

6,006 

0 

72 

0 

60,447 

1,226 

0 

Oct. 

5,564 

0 

2,622 

0 

0 

0 

0 

0 

55,695 

2,622 

0 

Nov. 

1,860 

2,942 

1,860 

0 

0 

0 

20 

0 

57,065 

1,860 

0 

Dec. 
Total  or 

1,875 

2,922 

1,875 

0 

0 

0 

0 

0 

55,613 

1.875 

0 

aversRC 

96,270 

52,963 

4,913 

34,488 

0 

984 

0 

52.963 

16,407 

1898 

Jan. 

2,453 

2,922 

2,453 

0 

0 

0 

0 

0 

54,261 

2.453 

0 

Feb. 

2,241 

2,922 

2,241 

0 

0 

0 

0 

0 

52,909 

2.241 

0 

Mar. 

2,131 

2,922 

2,131 

0 

0 

0 

0 

0 

51.687 

2,131 

0 

April 

1,950 

2,922 

1,950 

0 

448 

0 

34 

0 

50,335 

1,950 

0 

May 

2,213 

2,440 

2,213 

0 

462 

0 

39 

0 

48,836 

2,213 

0 

June 

1,159 

1.939 

1,159 

0 

448 

0 

39 

0 

47,232 

1.159 

0 

July 

672 

1,452 

672 

0 

464 

0 

40 

0 

45.627 

672 

0 

Aug. 

456 

948 

456 

0 

462 

0 

26 

0 

43,932 

456 

0 

Sept. 

467 

460 

467 

0 

448 

0 

12 

0 

42,267 

467 

0 

Oct. 

533 

0 

533 

0 

0 

0 

0 

0 

40,720 

533 

0 

Nov. 

580 

0 

580 

0 

0 

0 

0 

0 

39,189 

580 

0 

Doc. 
Total  or 

832 

0 

832 

0 

0 

0 

0 

0 

37,765 

832 

0 

average 

15,687 

15,687 

0 

2.732 

0 

190 

0 

15,687 

0 

1899 

Jan. 

1,414 

0 

1,414 

0 

0 

0 

0 

0 

36,413 

1.414 

0 

Feb. 

1,244 

0 

1,244 

■0 

0 

0 

0 

0 

3.5,061 

1.244 

0 

Mar. 

1,623 

0 

1,623 

0 

0 

0 

0 

0 

33,839 

1.623 

0 

April 

1,262 

0 

1,262 

0 

0 

0 

0 

0 

32.487 

1,262 

0 

May 

842 

0 

842 

0 

0 

0 

0 

0 

31.029 

842 

0 

June 

565 

0 

565 

0 

0 

0 

0 

0 

29.483 

S65 

0 

July 

221 

221 

0 

0 

0 

0 

0 

27.950 

221 

0 

Aug. 

295 

295 

0 

0 

0 

0 

0 

26.338 

295 

0 

Sept. 

220 

220 

0 

0 

0 

0 

0 

24,V52 

220 

0 

Oct. 

683 

683 

0 

0 

0 

0 

0 

23,268 

683 

0 

Nov. 

847 

847 

0 

0 

0 

0 

0 

21.787 

847 

0 

Dec. 
Total  or 

1,247 

c 

1.247 

0 

0 

0 

0 

0 

20,395 

1,247 

0 

average 

10.463 

1      10.463 

0 

0 

0 

0 

0 

10.463 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


383 


VOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

OVER- YEAR  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  13,  page  160.) 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000  acre-feet  capacity 

Yield 

Flood 
control 

Yield 

in  a 

Passed 

water 

in  a 
uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

Season- 
ally 
stored 
water  in 
aere-feet 

uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

by  dam 
for  prior 
rights 
(first  152 
seoond- 
feet  of 
natural 
flow)  in 
acre-feet 

passirg 
Azusa 
during 

flood 

season 

at  rates 

less  than 

1,900 
second- 

Season- 
ally 
stored 
water  in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Year  and 
month 

in 
acre-feet 

feet  in 
acre-feet 

in 
acre-feet 

1897 

0 

1,352 

0 

0 

122,650 

3,617 

10,611 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

109,519 

7,262 

4,478 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

114,649 

9,344 

0 

0 

2,520 

0 

0 

Mar. 

1,249 

1,309 

234 

0 

131,408 

9,042 

0 

0 

2,439 

363 

0 

April 

3,012 

1,352 

343 

0 

137,083 

8,126 

0 

0 

2,520 

494 

0 

May 

3,093 

1,309 

396 

0 

134,794 

4,033 

0 

0 

2,439 

583 

0 

June 

3,197 

1,352 

44? 

0 

131,772 

2,343 

0 

0 

2,520 

674 

0 

Jdly 

3,197 

1,352 

393 

0 

128,578 

1,613 

0 

0 

2,520 

621 

0 

Aug. 

3,153 

1,309 

290 

0 

125,437 

1,226 

0 

0 

2,439 

472 

0 

S'-pt. 

0 

1,352 

220 

0 

122,526 

2,622 

0 

0 

2,520 

357 

0 

Oct. 

0 

1,309 

143 

0 

122,591 

1,860 

0 

0 

2,439 

238 

0 

Nov. 

0 

1,352 

0 

0 

119,914 

1,875 

0 

0 

2,520 

0 

0 

Dec. 
Total  or 

16,901 

15,922 

2,466 

0 

52,963 

15,089 

0 

29,672 

3,802 

0 

average 
1898 

0 

1,352 

0 

0 

117,394 

2,453 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

114,874 

2,241 

0 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

112,598 

2,131 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

190 

0 

110,078 

1,950 

0 

0 

2,439 

313 

0 

April 

0 

1,352 

252 

0 

107,326 

2,213 

0 

0 

2,520 

410 

0 

May 

0 

1,309 

296 

0 

104,396 

1,159 

0 

0 

2,439 

490 

0 

June 

0 

1,352 

343 

0 

101,467 

672 

0 

0 

2,520 

565 

0 

July 

0 

1,352 

313 

0 

98,382 

456 

0 

0 

2,520 

516 

0 

Aug. 

0 

1,309 

238 

0 

95,346 

467 

0 

0 

2,439 

391 

0 

Sept. 

0 

1,352 

179 

0 

92,516 

533 

0 

0 

2,520 

293 

0 

Oct. 

0 

1,309 

115 

0 

89,703 

580 

0 

0 

2,439 

192 

0 

Nov. 

0 

1,352 

0 

0 

87,072 

832 

0 

0 

2,520 

0 

0 

Dec. 
Total  or 

0 

15,922 

1,926 

0 

15,687 

0 

0 

29,672 

3,170 

0 

average 
1899 

0 

1,352 

0 

0 

84,552 

1,414 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

82,032 

1,244 

0 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

79,756 

1,623 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,301- 

149 

0 

77,236 

1,262 

0 

0 

2,439 

246 

0 

April 

0 

1,352 

194 

0 

74,551 

842 

0 

0 

2,520 

325 

0 

May 

0 

1,309 

224 

0 

71,708 

565 

0 

0 

2,439 

383 

0 

June 

0 

1,352 

260 

0 

68,884 

221 

0 

0 

2,520 

440 

0 

July 

0 

1,352 

234 

0 

65,924 

295 

0 

0 

2,520 

399 

0 

Aug. 

0 

1,309 

175 

0 

63,005 

220 

0 

0 

2,439 

301 

0 

Sept. 

0 

1,352 

129 

0 

60,265 

683 

0 

0 

2,520 

224 

0 

Oct. 

0 

1,309 

83 

0 

57,521 

847 

0 

0 

2,439 

143 

0 

Nov. 

0 

1,352 

0 

0 

54,939 

1.247 

0 

0 

2,520 

0 

0 

Dec. 
Total  or 

0 

15,922 

1,448 

0 

10,463 

0 

0 

29,672 

2,461 

0 

average 

384 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  13a  (Continued).     SAN  GABRIEL 

WATER  YIELD  L^DER 

FLOOD  CONTROL.   SEASONAL  AND 
Monthly  Summary  of  Computa 

(^For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Max 

imum  flood  control  reserve  or 

first 

180,000  acie- 

131,000  acre-feet  of  capacity 

Flood 

v:.lj 

Flood 

control 

iieiu 

control 

Year  and 
month 

Run-off 

at 
Azusa 

in 
acre-feet 

Stage  of 
reser\-oir 
at  be- 
ginning 

of 
month  in 
acre-feet 

Passed 
by  dam 

for  prior 
rights 

(first  152 
secnnd- 
feet  of 
natural 
flow)  in 

acre-feet 

water 
passing 
Azusa 
during 
flood 
season 
at  rates 
less  than 

i.eoo 

second- 
feet  in 
acre-feet 

Season- 
ally 
"to red 
water  in 
acre-feet 

m  a 
uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
j'ear 
storage 

in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
wa> 
in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

Passed 
by  dam 

for  prior 
rights 

(first  152 
second- 
feet  of 
natural 
flow)  in 

acre-feet 

water 
passing 
Anjsa 
during 

flood 

season 

at  rates 

less  than 

1,900 
second- 
feet  in 
acre-feet 

1900 

Jan. 

1,968 

0 

1,968 

0 

0 

0 

0 

0 

19.043 

1.968 

0 

Feb. 

1,111 

0 

1,111 

0 

0 

0 

0 

0 

17,691 

1.111 

0 

Mar. 

1.230 

0 

1,230 

0 

0 

0 

0 

0 

16,469 

1,230 

0 

April 

1,012 

0 

1,012 

0 

0 

0 

0 

0 

15,117 

1.012 

0 

May 

2,275 

0 

2,275 

0 

0 

0 

0 

0 

13.713 

2.2".  5 

0 

June 

893 

0 

893 

0 

0 

0 

0 

0 

12,240 

893 

0 

July 

369 

0 

369 

0 

0 

0 

0 

0 

10,796 

369 

0 

Aug. 

246 

0 

246 

0 

0 

0 

0 

0 

9.295 

246 

0 

Sppt. 

238 

0 

238 

0 

0 

0 

0 

0 

7.820 

238 

0 

Oct. 

307 

0 

307 

0 

0 

0 

0 

0 

6.426 

307 

0 

Nov. 

11,068 

0 

1,058 

0 

0 

0 

0 

0 

5,018 

l.a58 

0 

Dec. 

1.269 

10.010 

1,269 

0 

0 

0 

0 

0 

13,687 

1,269 

0 

Total  or 

average 

21,986 

11,976 

0 

0 

0 

0 

0 

11,976 

0 

1901 

Jan. 

10,391 

10,010 

6,661 

12.810 

0 

0 

0 

0 

12,335 

6,661 

0 

Feb. 

38,709 

930 

8,350 

19.884 

0 

0 

0 

0 

14,713 

8.350 

0 

Mar. 

13,589 

11,405 

9,138 

0 

0 

0 

0 

0 

43,850 

9.138 

0 

April 

6,545 

15,856 

6,545 

0 

2.499 

0 

99 

0 

46,949 

6.545 

0 

May 

7,440 

13,258 

6,990 

0 

2.582 

0 

117 

0 

45,459 

6,990 

0 

June 

3,749 

11,009 

3,749 

0 

2,618 

0 

129 

0 

44.317 

3.749 

0 

July 

1,845 

8,262 

1,845 

0 

2.704 

0 

12ii 

0 

42,722 

1.845 

0 

Aug. 

1,240 

5,433 

1.240 

0 

2.704 

0 

79 

0 

41.041 

1.240 

0 

Sept. 

1.012 

2,650 

1,012 

0 

2.610 

0 

40 

0 

39.389 

1.012 

0 

Oct. 

1,476 

0 

1,476 

0 

0 

0 

0 

0 

37.850 

1,476 

0 

Nov. 

1,904 

0 

1,904 

0 

0 

0 

0 

0 

36.327 

1.904 

0 

Dec. 

1,660 

0 

1.660 

0 

0 

0 

0 

0 

34.909 

1.660 

0 

Total  or 

aveiagc 

89,560 

50.570 

32.694 

15.717 

0 

589 

0 

50.570 

0 

1902 

Jan. 

1,722 

0 

1.722 

0 

0 

0 

0 

0 

33,557 

1.722 

0 

Feb. 

2,055 

0 

2,055 

0 

0 

0 

0 

0 

32.205 

2.055 

0 

Mar. 

6,088 

0 

5.590 

0 

0 

0 

0 

0 

30.983 

5.590 

0 

.\pril 

3,028 

498 

3.928 

0 

72 

0 

8 

0 

30.129 

3.928 

0 

May 

2,398 

418 

2.398 

0 

73 

0 

11 

0 

28.679 

2.398 

0 

June 

1.190 

334 

1.190 

0 

72 

0 

12 

0 

27,143 

1.190 

0 

July 

676 

250 

676 

0 

74 

0 

12 

0 

25,620 

676'              0 

Aug. 

430 

164 

430 

0 

74 

0 

12 

0 

24,022 

430 !              0 

Sept. 

298 

78 

298 

0 

72 

0 

6 

0 

22,448 

298 

0 

Oct. 

430 

0 

430 

0 

0 

0 

0 

0 

20.972 

430 

0 

Nov. 

1.131 

0 

1.131 

0 

0 

0 

0 

0 

19.497 

1.131 

0 

Dec. 
Total  or 

1,968 

0 

1.968 

0 

0 

0 

0 

0 

18.111 

1.968 

0 

average 

22,314 1    - 

21.816 

0 

437 

0 

61 

»l 

21.816 

0 

THE    CONTROL   OF    FLOODS    BY    RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN.'' 

OVER- YEAR  STORAGE  COORDINATED. 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  13,  page  IbO.) 


385 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000 

acre-feet  capacity 

Yield 

Flood 
control 

Yield 

in  a 

Passed 

water 

in  a 

Season- 

uni- 
formly 
con- 

Evapora- 
tion 

Waste 

Stage  of 
reservoir 

by  dan. 

for  prior 
rights 

(first  1.52 
second- 
feet  of 
natural 
flow)  in 

acre-feet 

passing 
Azusa 

during 
fiiod 

season 

at  rates 

less  than 

1,900 

second- 

Season- 

uni- 
formly 
con- 

Evapora- 
tion 

Waste 

Year  iind 
month 

ally 

stored 
water  in 
acre-feet 

tinuous 
supply 
front, 
over- 
year 
storage 

from 
reservoir 
surface 

in 
acre-feet 

over 
spill- 
way 

in 
acre-feet 

at  be- 
ginning 

of 
month  in 
acre-feet 

ally 

stored 

waterin 

acre-feet 

tinuous 
supply 
from 
over- 
year 
storage 

from 
reservoir 
surface 

in 
acre-feet 

over 
spill- 
way 
in 
acre-feet 

in 
acre-feet 

feet  in 
acre-feet 

in 
acre-feet 

1900 

0 

1,352 

0 

0 

52,419 

1,968 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

49,899 

1.111 

0 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

47,623 

1.230 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

95 

0 

45,103 

1,012 

0 

0 

2,439 

176 

0 

April 

0 

1,352 

121 

0 

42,488 

2,275 

0 

0 

2.520 

230 

0 

May 

0 

1,309 

135 

0 

39,738 

893 

0 

0 

2.439 

264 

0 

June 

0 

1,352 

149 

0 

37,035 

369 

0 

0 

2,520 

299 

0 

July 

0 

1,352 

123 

0 

34,216 

246 

0 

0 

2,520 

268 

0 

Aug. 

0 

1,309 

85 

0 

31,428 

238 

0 

0 

2.439 

200 

0 

Sept. 

0 

1,352 

56 

0 

28,789 

307 

0 

0 

2,520 

145 

0 

Oct. 

0 

1,309 

32 

0 

26,124 

1,058 

0 

0 

2,439 

95 

0 

Nov. 

0 

1,352 

0 

0 

33.600 

1,269 

0 

0 

2.520 

0 

0 

Dec. 
Total  or 

0 

15,922 

796 

0 

11,976 

0 

0 

29.672 

1.677 

0 

average 
1901 

0 

1,352 

0 

0 

31,080 

6,661 

0 

0 

2.520 

0 

0 

Jan. 

0 

1,222 

0 

0 

32,290 

8,350 

0 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

60,373 

9,138 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

181 

0 

62,304 

6,545 

0 

0 

2,439 

214 

0 

April 

0 

1,352 

240 

0 

59,651 

6,990 

0 

0 

2,520 

284 

0 

May 

0 

1,309 

286 

0 

57,297 

3,749 

0 

0 

2,439 

331 

0 

June 

0 

1,352 

329 

0 

54,527 

1,845 

0 

0 

2,520 

381 

0 

July 

0 

1,352 

300 

0 

51,626 

1,240 

0 

0 

2,520 

341 

0 

Aug. 

0 

1,309 

230 

0 

48,765 

1,012 

0 

0 

2,439 

256 

0 

Sept. 

0 

1,352 

171 

0 

46,070 

1,476 

0 

0 

2,520 

188 

0 

Oct. 

0 

1.309 

109 

0 

43.362 

1,904 

0 

0 

2,439 

121 

0 

Nov. 

0 

1,352 

0 

0 

40.802 

1,660 

0 

0 

2,520 

0 

0 

Dec. 

Tnfnl  nr 

0 

15,922 

1,846 

0 

50,570 

0 

0 

29,672 

2,116 

0 

1  ULdl  Ul 

average 
1902 

0 

1,352 

0 

0 

38,282 

1,722 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

35,762 

2,055 

0 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

33,486 

5,.590 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

141 

0 

31,464 

3,928 

0 

0 

2,439 

143 

0 

April 

0 

1,352 

184 

0 

28,882 

2,398 

0 

0 

2„520 

182 

0 

May 

0 

1,309 

214 

0 

26,180 

1,190 

0 

0 

2.439 

208 

0 

June 

0 

1,352 

246 

0 

23,533 

676 

0 

0 

2.520 

232 

0 

July 

0 

1,352 

222 

0 

20,781 

430 

0 

0 

2,520 

202 

0 

Aug. 

0 

1,309 

167 

0 

18,059 

298 

0 

0 

2.439 

145 

0 

Sept. 

0 

1,352 

123 

0 

15,475 

430 

0 

0 

2.520 

99 

0 

Oct. 

0 

1,309 

77 

0 

12,850 

1,131 

0 

0 

2,439 

58 

0 

Nov. 

0 

1,352 

0 

0 

10,359 

1,968 

0 

0 

2.520 

0 

0 

Dec. 
Total  or 
average 

0 

15,922 

1.374 

0 

21,816 

0 

0 

29.672 

1,269 

0 

^86 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  13a  (Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL,  SEASONAL  AND 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  control  reserve  or 

first 

131,000  acre-feet  of  capacity 

1 80,uuu  acre- 

Flood 

Yield 

Flood 

control 

control 

Run-off 

at 
Azusa 

in 
acre-feet 

Passed 

water 

in  a 

Passed 

water 

Year  and 
month 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

by  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 

passing 
Azusa 
during 

flood 

season 

at  rates 

less  than 

1,900 

Se.ison- 

ally 

stored 

water  in 

acre-feet 

uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

ty  dam 
for  prior 

rights 
(first  152 
second - 

feet  of 
natural 
flow)  in 

passing 
Azusa 
during 

flood 

season 

at  rates 

less  than 

1.900 

acre-feet 

second- 

acre-feet 

second- 

feet  in 
acre-feet 

in 
acre-feet 

feet  in 
acre-feet 

1903 

Jan. 

9,100 

0 

2,536 

4,8o6 

0 

0 

0 

0 

16.759 

2.536 

0 

Feb. 

5,665 

1,708 

5.497 

1,189 

0 

0 

0 

0 

21.971 

5,497 

0 

Mar. 

15,802 

687 

7,898 

0 

0 

0 

0 

0 

20.917 

7,898 

0 

April 

47,127 

8,591 

9,042 

0 

1,344 

0 

67 

0 

27.469 

9,042 

0 

May 

13,343 

45,265 

9,110 

0 

8,963 

0 

244 

0 

64,065 

9.116 

(I 

June 

5,653 

40,285 

5,653 

0 

9,703 

0 

272 

0 

66,633 

5,653 

0 

July 

2,644 

30.310 

2,644 

0 

10.026 

0 

270 

0 

63.947 

2,644 

0 

Aug. 

1,783 

20,014 

1,783 

0 

10,026 

0 

202 

0 

61,067 

1,783 

0 

Sept. 

1,488 

9,786 

1,488 

0 

9,685 

0 

101 

0 

58,291 

1,488 

0 

Oct. 

1,476 

0 

1,476 

0 

0 

0 

0 

0 

55,623 

1.470 

0 

Nov. 

1,428 

0 

1,428 

0 

0 

0 

0 

0 

54,057 

1,428 

0 

Dec. 

1,4/6 

0 

1,4,6 

0 

0 

0 

0 

0 

52.609 

1,476 

0 

Total  or 

average 

106,980 

50,037 

6.045 

49.74 ( 

0 

1.156 

0 

50,037 

0 

1904 

Jan. 

1,500 

u 

1,500 

0 

0 

0 

0 

0 

51.257 

1,500 

0 

Feb. 

2,744 

0 

2.177 

0 

0 

0 

0 

0 

49.905 

2,177 

0 

Mar. 

6,813 

567 

4,724 

0 

0 

0 

0 

0 

49.207 

4,724 

0 

April 

5,337 

2,656 

5,337 

0 

407 

0 

29 

0 

49.944 

5,337 

0 

May 

4,089 

2,220 

4.089 

0 

420 

0 

37 

0 

48,447 

4,089 

0 

Juno 

1,517 

1,763 

1,517 

0 

407 

0 

36 

0 

46,845 

1,517 

0 

July 

861 

1,320 

861 

0 

420 

0 

36 

0 

45.240 

861 

0 

Aug. 

793 

804 

793 

0 

420 

0 

24 

0 

43.545 

793 

0 

Sept 

643 

420 

643 

(I 

408 

0 

12 

0 

41,880 

643 

0 

Oct. 

738 

0 

738 

0 

0 

0 

0 

0 

40.333 

738 

(1 

Nov. 

762 

0 

762 

0 

0 

0 

0 

0 

38,802 

762 

0 

Dec. 
Total  or 

1.039 

0 

1.039 

0 

0 

0 

0 

0 

37,378 

1.039 

0 

average 

26,836 

24.180 

0 

2.482 

0 

174 

0 

24.180 

0 

1905 

Jan. 

2,251 

0 

2.251 

0 

0 

0 

0 

0 

36.026 

2.251 

0 

Feb. 

25,880 

0 

8.206 

11.798 

0 

0 

0 

0 

34,674 

8,206 

0 

Mar. 

75,140 

5,876 

9.281 

18.198 

0 

0 

0 

0 

51.126 

9.281 

13,658 

April 

19,580 

53,537 

9.042 

0 

8.727 

0 

197 

0 

101.975 

9.042 

0 

May 

17,090 

55,151 

9.344 

0 

10.942 

0 

274 

0 

104.952 

9.344 

0 

June 

8,271 

51,681 

7.960 

0 

12.475 

0 

313 

0 

102.698 

7.960 

0 

July 

5,103 

39.204 

5.103 

U 

12,989 

0 

313 

0 

91.355 

5.103 

0 

Aug. 

2.631 

25.902 

2.631 

0 

12,989 

0 

232 

0 

79.225 

2.631 

0 

Sept. 

1,869 

12.681 

1.689 

0 

12,560 

0 

121 

0 

67,175 

1.869 

0 

Oct. 

1.770 

0 

1.770 

0 

0 

0 

0 

u 

55.631 

1.770 

0 

Nov. 

2,660 

U 

2,660 

0 

0 

0 

0 

0 

54.065 

2.660 

0 

Dec. 
Total  or 
average 

2,470 

0 

2,470 

0 

0 

0 

0 

0 

52,617 

2,470 

0 

164.7I5J 

62.687 

29.906 

70,682 

" 

1.450 

0 

62,587 

13,658 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

OVER- YEAR  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  13,  page  160.) 


387 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


I 


feet  capacity 

240,000 

icre-f  eet  capacity 

Yield 

Flood 
control 

Yield 

in  a 

Passed 

water 

in  a 

Season- 

uni- 
formly 
con- 

Evapora- 
tion 

Waste 

Stage  of 
reservoir 

by  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 
acre-feet 

passing 
Azusa 
during 
flood 
season 
at  rates 
less  than 

1.900 
second- 

Season- 

uni- 
formly 
con- 

Evapora- 
tion 

Waste 

Year  and 
month 

ally 

stored 

water  in 

acre-feet 

tinuous 
supply 
from 
over- 
year 
storage 

from 
reservoir 
surface 

in 
acre-feet 

over 
spill- 
way 
in 
acre-feet 

at  be- 
ginning 

of 
month  in 
acre-feet 

ally 

stored 

water  in 

acre-feet 

tinuous 
supply 
from 
over- 
year 
storage 

from 
reservoir 
surface 

in 
acre-feet 

over 
spill- 
way 
in 
acre-feet 

m 
acre-feet 

feet  in 
acre-feet 

in 
acre-feet 

1903 

0 

1,352 

0 

0 

/,839 

2,536 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

11,883 

5,497 

0 

0 

2,276 

0 

0 

Feb. 

0 

1.352 

0 

0 

9,775 

7,898 

0 

0 

2,520 

0 

0 

Mar 

0 

1.309 

180 

0 

15,159 

9,042 

0 

0 

2,439 

171 

0 

April 

0 

1,352 

307 

0 

50,634 

9,116 

0 

0 

2.520 

268 

0 

May 

1.012 

1,309 

365 

0 

52,073 

5,653 

0 

0 

2,439 

311 

0 

June 

1,107 

1,352 

421 

0 

49,323 

2,644 

0 

0 

2,520 

359 

0 

July 

1,045 

1,352 

379 

0 

46,444 

1,783 

0 

0 

2,520 

321 

0 

Aug. 

1.071 

1.309 

288 

0 

43,603 

1,488 

0 

0 

2,439 

240 

0 

Sept. 

0 

1.352 

214 

0 

40,924 

1,476 

0 

0 

2,520 

176 

0 

Oct. 

0 

1,309 

139 

0 

38,228 

1,428 

0 

0 

2,439 

113 

0 

Nov. 

0 

1,352 

0 

0 

35,676 

1,476 

0 

0 

2,520 

0 

0 

Dec. 
Total  nr 

4,235 

15,922 

2.293 

0 

50,037 

0 

0 

29,672 

1,959 

0 

average 
1904 

0 

1,352 

0 

0 

33,156 

1,500 

0 

0 

.   2,520 

0 

0 

Jan. 

0 

1,265 

0 

0 

30,636 

2,177 

0 

0 

2,358 

0 

0 

Feb. 

0 

1,352 

0 

0 

28,845 

4,724 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

188 

0 

28,414 

5,337 

0 

0 

2,439 

135 

0 

April 

0 

1,352 

250 

0 

25,840 

4,089 

0 

0 

2,520 

173 

0 

May 

0 

1,309 

296 

0 

23,147 

1,517 

0 

0 

2,439 

194 

0 

June 

0 

1,352 

343 

0 

20,514 

861 

0 

0 

2,520 

216 

0 

July 

0 

1,352 

313 

0 

17,778 

793 

0 

0 

2,520 

184 

0 

Aug. 

0 

1,309 

238 

0 

15,074 

643 

0 

0 

2.439 

129 

0 

Sept. 

0 

1,352 

179 

0 

12.506 

738 

0 

0 

2,520 

87 

0 

Oct. 

0 

1.309 

115 

0 

9,899 

762 

0 

0 

2,439 

50 

0 

Nov. 

0 

1,352 

0 

0 

7.410 

1,039 

0 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

0 

15.965 

1,922 

0 

21,180 

0 

0 

29.754 

1,168 

0 

1905 

0 

1.352 

0 

0 

4,890 

2.251 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

2,370 

8,206 

0 

0 

2,276 

0 

0 

Feb. 

0 

1.352 

0 

0 

17,768 

9,281 

0 

0 

2.520 

0 

0 

Mar. 

5,949 

1,309 

303 

0 

81,107 

9,042 

0 

0 

2,439 

268 

0 

April 

8,237 

1,352 

411 

0 

88,938 

9,344 

0 

0 

2,520 

377 

0 

May 

9,875 

1,309 

470 

0 

93,787 

7,960 

0 

0 

2,439 

464 

0 

June 

10,266 

1,352 

512 

0 

91,195 

5.103 

0 

0 

2,520 

527 

0 

July 

10,266 

1,352 

432 

0 

88,148 

2.631 

0 

0 

2,520 

482 

0 

Aug. 

9.935 

1,309 

300 

0 

85,146 

1,869 

0 

0 

2,439 

365 

0 

Sept. 

0 

1,352 

214 

0 

82,342 

1,770 

0 

0 

2,520 

272 

0 

Oct. 

0 

1,309 

139 

0 

79,550 

2,660 

0 

0 

2,439 

176 

0 

Nov. 

0 

1,352 

0 

0 

76.935 

2,470 

0 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

54,528 

15,922 

2.781 

0 

62.587 

0 

0 

29,672 

2,931 

0 

388  WATER   RESOURCES   OF    CALIFORNIA. 

TABLE   13a  f Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL,  SEASONAL  AND 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  control 

reserve  or 

first 

IgQ  t\nn  ....PA- 

131,000  acre-feet  of  capacity 

Flood 

Yield 

Flood 

control 

control 

Run-off 

at 
Azusa 

in 
acre-feet 

Passed 

water 

in  a 

Passed 

water 

Year  and 
month 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

by  dim 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 

pissing 
Azusa 

during 
flood 

season 

at  rates 

less  than 

1,900 

Season- 
ally 
stored 
waterin 
acre-feet 

uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre  feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

by  dim 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 

passing 
Azusa 

during 
flood 

season 

at  rates 

less  than 

1.900 

acre-feet 

second- 

acre-feet 

second- 

feet  in 

in 
acre-feet 

feet  in 

acre-feet 

acre-feet 

1906 

Jan. 

4,240 

0 

3,633 

0 

0 

0 

0 

0 

51.265 

3.633 

0 

Feb. 

3.960 

607 

3.960 

0 

0 

0 

0 

0 

50.520 

3.960 

0 

Mar. 

129,000 

607 

7,561 

24,303 

0 

0 

0 

0 

49,298 

7.561 

23.965 

April 

34,600 

97.713 

9,042 

19,634 

11,660 

0 

274 

0 

145,420 

9.042 

15.432 

May 

21,000 

91.733 

9,344 

0 

18,263 

0 

375 

0 

140.852 

9.314 

0 

June 

15.500 

84,751 

9,042 

0 

20,518 

0 

426 

0 

135.105 

9.042 

0 

July 

9,350 

70,265 

8.664 

0 

22,606 

0 

452 

0 

121,812 

8.664 

0 

Aug. 

4,490 

47,893 

4,490 

0 

24,086 

0 

329 

0 

100,040 

4.490 

0 

Sept. 

2,840 

23,478 

2,840 

0 

23,305 

0 

173 

0 

57,426 

2.840 

0 

Oct. 

2,450 

0 

2,450 

0 

0 

0 

0 

0 

55,759 

2.450 

0 

Nov. 

2,400 

0 

2,400 

0 

0 

0 

0 

0 

54,193 

2.400 

0 

Dec. 

11,600 

0 

4,030 

0 

0 

0 

0 

0 

52,745 

4.030 

0 

Total  or 
average 

241,430 

"  67,456 

43,937 

120,438 

0 

2.029 

0 

67,456 

39.397 

1907 

Jan. 

58,400 

7,570 

0,217 

50,881 

0 

0 

0 

0 

58,963 

9,217 

51.921 

Feb. 

47,100 

5,872 

8,439 

31,125 

0 

0 

0 

0 

54,873 

8,439 

29.904 

Mar. 

116,000 

13,408 

9,344 

47,166 

0 

0 

0 

0 

62.408 

9,344 

45.814 

.\pril 

58,400 

72,898 

9,042 

0 

11,708 

0 

238 

0 

121,898 

9,042 

0 

May 

21,500 

110.310 

9,344 

0 

21,989 

0 

426 

0 

160,351 

9,344 

0 

June 

15,100 

100,051 

9,042 

0 

24,242 

0 

478 

0 

151,129 

9,042 

0 

July 

8,360 

81,389 

7,920 

0 

27,072 

0 

493 

0 

133.496 

7,920 

0 

Aug. 

5,390 

54.264 

5,390 

0 

27,300 

0 

359 

0 

107,476 

5,390 

0 

S3pt. 

3,580 

26.605 

3,580 

0 

26,421 

0 

184 

0 

81,011 

3.580 

0 

Oct. 

4,090 

0 

4,090 

0 

0 

0 

0 

0 

55.644 

4.090 

0 

Nov. 

3.800 

0 

3,800 

0 

0 

0 

0 

0 

54.078 

3.800 

0 

Dec. 

3,600 

0 

3,600 

0 

0 

0 

0 

0 

52.630 

3.600 

0 

Totel  or 
average 

345,320 

82,808 

129,172 

138,732 

0 

2.178 

0 

82.808 

127.639 

1908 

Jan. 

11,100 

0 

4,973 

4,617 

0 

0 

0 

0 

51.278 

4.973 

5.543 

Feb. 

15,000 

1.510 

8,741 

5,141 

0 

0 

0 

0 

50.510 

8.741 

4,616 

Mar. 

12,700 

2.628 

9,255 

0 

0 

0 

0 

0 

58.888 

9.255 

0 

April 
May 

9.280 

6.073 

8,656 

0 

052 

0 

52 

0 

52,981 

8.656 

0 

7.190 

5.693 

7,1.39 

0 

1,106 

0 

69 

0 

52,100 

7.139 

0 

June 

4.190 

4.569 

4,190 

0 

1.071 

0 

61 

0 

50,537 

4.190 

0 

July 

2.560 

3.437 

2,560 

0 

1.106 

0 

57 

0 

48.919 

2.560 

0 

Aug. 

2.210 

2.274 

2,210 

0 

1.106 

0 

36 

0 

47.208 

2.210 

0 

Sspt. 

1.820 

1.132 

1,820 

0 

1,120 

0 

12 

0 

45.531 

1.820 

0 

Oct. 

2.070 

0 

2.070 

0 

0 

0 

0 

0 

43.970 

2,070 

0 

Nov. 

1.960 

0 

1,960 

0 

0 

0 

0 

0 

42.432 

1,960 

0 

Dec. 

2.870 

0 

2,870 

0 

0 

0 

0 

0 

41.000 

2.870 

0 

Total  or 
average 

72.950 1 

56,444 

9,758 

6.461 

0 

287 

0 

56.444 

10,159 

THE   CONTROL   OF    FLOODS   BY    RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

OVER- YEAR  STORAGE  COORDINATED. 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  13,  page  160.) 


389 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000 

acre-feet  capacity 

Yield 

Flood 
control 

Yield 

in  a 

Passed 

water 

in  a 

Season- 
ally 
stored 
water  in 

uni- 
formly 

con 
tinuous 
supply 

from 

E-.  apora- 

tion 

from 

reservoir 

surface 

Waste 
over 
spill- 
wiy 

Stage  of 
reservoir 
at  be- 
ginning 
of 

by  dam 
for  prior 
rights 
f  first  152 
second- 
feet  of 
natural 
flow)  in 
acre-feet 

passing 
Azusa 

during 
flood 

season 

Season- 
ally 
stored 
waterin 

uni- 
formly 

con- 
tinuous 
supply 

from 

Evapora- 
tion 
from 
reservoir 
surface 

Waste 
over 
spill- 
way 

Year  and 
month 

acre-feet 

over- 
year 
storage 

in 

acre-feet 

in 
acre-feet 

month  in 
acre-feet 

at  rates 
less  than 

1,900 
second- 

acre-feet 

over- 
year 
storage 

in 
acre-feet 

in 
acre-feei 

in 
acre-feet 

feet  in 
acre-feet 

in 
acre-feel 

1906 

0 

1,352 

0 

0 

74,415 

3,633 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

72,502 

3,960 

0 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

70,226 

7,561 

9,428 

0 

2,520 

0 

0 

Mar. 

13,028 

1,309 

357 

0 

179,71V 

9,042 

0 

6,365 

2,439 

444 

0 

April 

1,5,553 

1,352 

498 

0 

196,027 

9,344 

0 

11,680 

2,520 

636 

0 

May 

ir,843 

1,309 

569 

0 

192.847 

9,042 

0 

14,159 

2,439 

755 

0 

June 

20,527 

1,352 

609 

0 

181,952 

8,664 

0 

16,782 

2,520 

857 

0 

July 

20,774 

1,352 

488 

0 

162,479 

4,490 

0 

17,151 

2,520 

734 

0 

Aug. 

20,043 

1,309 

315 

0 

142,074 

2,840 

0 

16,587 

2,439 

518 

0 

Sjpt. 

0 

1,352 

214 

0 

122,530 

2,450 

0 

0 

2,520 

357 

0 

Oct. 

0 

1,309 

139 

0 

119,653 

2,400 

0 

0 

2,439 

235 

0 

Nov. 

0 

1,352 

0 

0 

116,979 

4,030 

0 

0 

2,520 

0 

0 

Dec. 

Total  or 
average 

107,768 

15,922 

3,189 

0 

67,456 

9,428 

82,724 

29,672 

4,536 

0 

1907 

0 

1,352 

0 

0 

122,029 

9,217 

53,819 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

114,873 

8,439 

28,878 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

122,380 

9,344 

44,618 

0 

2,520 

0 

0 

Mar. 

9,221 

1,309 

375 

0 

181,898 

9,042 

230 

6,475 

2,439 

446 

0 

April 

19,487 

1,352 

539 

0 

221,606 

9,344 

0 

16,826 

2,520 

698 

0 

May 

21,773 

1,309 

609 

0 

213,718 

9,042 

0 

19,251 

2,439 

815 

0 

June 

24,466 

1,352 

642 

0 

197,271 

7,920 

0 

21,922 

2,520 

906 

0 

July 

24,651 

1,352 

462 

0 

172,363 

5,390 

0 

22,149 

2,520 

766 

0 

Aug. 

23,737 

1,309 

321 

0 

146,928 

3,580 

0 

21,428 

2,439 

531 

0 

Sept. 

0 

1,352 

214 

0 

122,530 

4,090 

0 

0 

2,520 

357 

0 

Oct. 

0 

1,309 

139 

0 

119,653 

3,800 

0 

0 

2,439 

236 

0 

Nov. 

0 

1,352 

0 

0 

116,978 

3,600 

0 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

123,335 

15,922 

3,301 

0 

82,808 

127,605 

108,051 

29,672 

4,755 

0 

1908 

0 

1,352 

0 

0 

114,4.58 

4,973 

7,555 

0 

2,520 

0 

0 

Jan. 

0 

1,265 

0 

0 

110,510 

8,741 

4,224 

0 

2,358 

0 

0 

Feb. 

0 

1,352 

0 

0 

110,187 

9,255 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

196 

0 

111,112 

8,656 

0 

0 

2,439 

317 

0 

April 

0 

1,352 

262 

0 

108.980 

7,139 

0 

0 

2,520 

420 

0 

May 

0 

1,309 

309 

0 

106,091 

4,190 

0 

0 

2,439 

494 

0 

June 

0 

1,352 

359 

0 

103,158 

2,560 

0 

0 

2,520 

573 

0 

July 

0 

1,352 

325 

0 

100,065 

2,210 

0 

0 

2,520 

524 

0 

Aug. 

0 

1,309 

252 

0 

97,021 

1,820 

0 

0 

2,439 

397 

0 

Sept. 

0 

1,352 

183 

0 

94,!85 

2,070 

0 

0 

2,520 

297 

0 

Oct. 

0 

1,309 

123 

0 

91,368 

1,960 

0 

0 

2,439 

194 

0 

Nov. 

0 

1,352 

0 

0 

88,735 

2,870 

0 

0 

2,520 

0 

0 

Dec. 
Tola'  or 
average 

0 

15,965 

2,012 

0 

56.444 

11,779 

0 

29,754 

3,216 

0 

390 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  13a  (Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL,  SEASONAL  AND 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Max 

Imum  flood  control  reserve  or 

first 

iQn 

131,000  acre-feet  of  capacity 

1  oU,uuu  abi  o- 

Flood 

Yield 

Flood 

control 

control 

Run-off 

at 
Azusa 

in 
acre-feet 

Passed 

water 

in  a 

Passed 

water 

Year  and 
rr.onth 

Stage  of 
reservoir 
at  be- 
ginning 
of 

by  dam 
for  prior 

riahts 
(first  152 
pecond- 

feet  of 

passing 
Azusa 

during 
flood 

season 

at  rates 

Season- 
ally 
stored 
watcrin 
acre-feet 

uni- 
formly 

con- 
tinuous 
pupply 

from 

Evapora- 
tion 
from 
reservoir 
surface 

Waste 
over 
spill- 
way 
in 

Stage  of 

reservoir 

at  be- 

ginnii'g 

of 
month  in 
acre-feet 

by  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 

passing 
Azusa 
during 
flood 
season 
at  rates 

month  in 
acre-feet 

natural 
flow)  in 

less  than 
1,900 

over- 
year 

storage 

in 

acre-feet 

acre-feet 

natural 
flow)  in 

less  than 
1,900 

acre-feet 

second- 

acre-feet 

second- 

feet  in 

in 
acre-feet 

feet  in 

acre-feet 

acre-feet 

1909 

Jan. 

25,500 

0 

5,596 

19,385 

0 

0 

0 

0 

39,648 

5.596 

8,681 

Feb. 

5!),400 

519 

8,440 

42,858 

0 

0 

0 

0 

49.519 

8.440 

41,897 

Mar. 

26,300 

8,621 

9,344 

0 

0 

0 

0 

0 

57,360 

9.344 

0 

April 

28,000 

25,577 

9,042 

0 

4,003 

0 

131 

0 

72,964 

9.042 

0 

May 

15.200 

40,341 

9,344 

0 

7,980 

0 

228 

0 

89.165 

9,344 

0 

June 

8,570 

37,989 

8,319 

0 

9,144 

0 

260 

0 

88,259 

8,319 

0 

July 

5,040 

28,830 

5,040 

0 

9,528 

0 

264 

0 

80,467 

5,040 

0 

Aug. 

3,120 

19,044 

3,120 

0 

9,528 

0 

196 

0 

71,998 

3,120 

0 

Sept. 

2,320 

9,320 

2,320 

0 

9.225 

0 

95 

0 

63,656 

2,320 

0 

Oct. 

2.310 

0 

2,310 

0 

0 

0 

0 

0 

55.087 

2,310 

0 

Nov. 

2,880 

0 

2,880 

0 

0 

0 

0 

0 

54.121 

2,880 

0 

Dec. 
Total  or 
average 

20,900 

0 

0,346 

0 

0 

0 

0 

0 

62,673 

6,346 

1,682 

199,540 

72,101 

62,243 

49,408 

0 

1,174 

0 

72,101 

52,260 

1910 

Jan. 

09,500 

14,554 

9,344 

73,583 

0 

0 

0 

0 

64,193 

9.344 

72.870 

Feb. 

11,500 

1,127 

8,435 

2,089 

0 

0 

0 

0 

50,127 

8,435 

2.292 

Mar. 

9.590 

1,503 

9,029 

0 

0 

0 

0 

0 

49,678 

9.029 

0 

April 

8,270 

2,064 

8.120 

0 

321 

0 

22 

0 

48,887 

8,120 

0 

May 

5.050 

1,871 

5,050 

0 

363 

0 

29 

0 

47,542 

5.050 

0 

June 

3,500 

1,479 

3,500 

0 

352 

0 

14 

0 

45,940 

3,560 

0 

July 

2,450 

1,113 

2,450 

0 

363 

0 

16 

0 

44.340 

2,450 

0 

Aug. 

1,710 

734 

1,710 

0 

363 

0 

16 

0 

42.051 

1,710 

0 

Sept. 

1,370 

355 

1,370 

0 

355 

0 

0 

0 

40.992 

1,370 

0 

Oct. 

1,500 

0 

1.560 

0 

0 

0 

0 

0 

39,449 

1,560 

0 

Nov. 

1,870 

0 

1,870 

0 

0 

0 

0 

0 

37.923 

1,870 

0 

Dec. 
Total  or 
average 

2,020 

0 

2.020 

0 

0 

0 

0 

0 

36.501 

2,020 

0 

118,450 

54,518 

76,272 

2,117 

0 

97 

0 

54.518 

75,162 

1911 

Jan. 

37,200 

0 

6,441 

7,031 

0 

0 

0 

0 

35,149 

6.441 

6.949 

Feb. 

44,300 

23,728 

8,440 

53,874 

0 

0 

0 

0 

57,007 

8,440 

38.010 

Mar. 

122,000 

5,714 

9,.341 

57,434 

0 

0 

0 

0 

54.235 

9,344 

55,867 

April 

28,200 

60,930 

9,012 

0 

9,774 

0 

212 

0 

109,082 

9,012 

0 

May 

10,000 

70,108 

9,344 

0 

13,936 

0 

317 

0 

120,008 

9.344 

0 

June 

7,500 

63.111 

7,322 

0 

15,247 

0 

357 

0 

114.155 

7,322 

0 

July 

5,230 

47,685 

5,230 

0 

15,816 

0 

355 

0 

99.851 

5,230 

0 

Aug. 

3,010 

31.514 

3,010 

0 

15,816 

0 

260 

0 

84.807 

3,610 

0 

Sept. 

2,830 

16.438 

2,830 

0 

15.303 

0 

135 

0 

69.915 

2,830 

0 

Oct. 

3,140 

0 

3.140 

0 

0 

0 

0 

0 

55.688 

3,140 

0 

Nov. 

2,800 

0 

2,800 

0 

0 

0 

0 

0 

64.121 

2,800 

0 

Dec. 

2,870 

0 

2.870 

0 

0 

0 

0 

0 

52,673 

2,870 

0 

Total  or 
average 

276,280 

70,413 

118,339 

85,892 

0 

1.636 

0 

70,413 

100,816 

THE   CONTROL   OP   FLOODS   BY    RESERVOIKS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

OVER- YEAR  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  13,  page  160.) 


391 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000  acre-feet  capacity 

Yield 

Flood 
control 

Yield 

in  a 

Passed 

■water 

in  a 

Season- 
ally 
stored 
water  in 
acre-feet 

uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

by  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
fiow)  in 
aere-feet 

passing 
Azusa 
during 
flood 
season 
at  rates 

less  than 

1,900 
second- 
feet  in 

acre-feet 

Season- 
ally 
stored 
water  in 
acre-feet 

formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Year  and 
month 

1909 

0 

1,352 

0 

0 

86,215 

5,596 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

103,599 

8,440 

35,296 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

116,987 

9,344 

0 

0 

2,520 

0 

0 

Mar. 

1,190 

1,309 

258 

0 

131,423 

9,042 

0 

0 

2,439 

375 

0 

April 

5,041 

1,352 

369 

0 

147,567 

9,344 

0 

1,955 

2  520 

520 

0 

May 

G,306 

1,309 

428 

0 

148,428 

8,319 

0 

3,318 

2,439 

629 

0 

June 

6,639 

1,352 

478 

0 

142,293 

5,040 

0 

3,515 

2,520 

720 

0 

July 

6,578 

1,352 

412 

0 

135,538 

3,120 

0 

3,515 

2,520 

646 

0 

Aug. 

6.365 

1,309 

295 

0 

128,857 

2,32a 

0 

3,403 

2,439 

485 

0 

Sept. 

0 

1,352 

214 

0 

122,530 

2,310 

0 

0 

2,520 

357 

0 

Oct. 

0 

1,309 

139 

0 

119,653 

2,880 

0 

0 

2.439 

236 

0 

Nov. 

0 

1,352 

0 

0 

116,978 

6,346 

3.425 

0 

2,520 

0 

0 

Dec. 

Total  or 
average 

32,119 

15.922 

2,593 

0 

72,101 

38.721 

15,706 

29,672 

3.968 

0 

1910 

0 

1,352 

0 

0 

125,587 

9,344 

73,110 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

110,113 

8,435 

1,945 

0 

2,276 

0 

u 

Feb. 

0 

1,352 

0 

0 

108,957 

9,029 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

186 

0 

106,998 

8,120 

0 

0 

2,439 

307 

0 

April 

0 

1,352 

250 

0 

104,402 

5,050 

0 

0 

2,520 

407 

0 

May 

0 

1,309 

291 

0 

101,475 

3,560 

0 

0 

2,439 

478 

0 

June 

U 

1,352 

337 

0 

98,558 

2,450 

0 

0 

2,520 

555 

0 

July 

0 

1.352 

307 

0 

95,483 

1,710 

0 

0 

2,520 

506 

0 

.^.ug. 

0 

1,309 

234 

0 

92,457 

1,370 

0 

0 

2.439 

385 

0 

Sept. 

0 

1,352 

174 

0 

89,633 

1,560 

0 

0 

2,520 

288 

0 

Oct. 

0 

1,309 

113 

0 

86,825 

1,870 

0 

0 

2,439 

188 

0 

Nov. 

0 

1,352 

0 

0 

84,198 

2,020 

0 

0 

2,520 

0 

0 

Dec. 

Total  or 

0 

15,922 

1,892 

0 

54,518 

75,055 

0 

29,672 

3,114 

0 

average 
1911 

0 

1,352 

0 

0 

81,678 

6,441 

0 

0 

2,520 

0 

0 

Jan. 

0 

1.222 

0 

0 

109.917 

8.440 

29,679 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

113,822 

9,,344 

55,275 

0 

2,520 

0 

0 

Mar. 

7,198 

1,.309 

325 

0 

168,683 

9,042 

0 

4.557 

2,439 

424 

0 

April 

11,311 

1,352 

446 

0 

180,421 

9,344 

0 

8,550 

2  520 

599 

0 

May 

12,671 

1,309 

502 

0 

176,008 

7,.322 

0 

10,018 

2,439 

708 

0 

June 

13,155 

1,352 

537 

0 

162,991 

5,230 

0 

10.444 

2,520 

793 

0 

July 

13,094 

1,352 

446 

0 

149,234 

3.610 

0 

10,444 

2,520 

692 

0 

Aug. 

12,612 

1,.309 

306 

0 

135,578 

2,830 

0 

10,109 

2,4.39 

500 

0 

Sept. 

0 

1,352 

215 

0 

122,5.30 

3,140 

0 

0 

2,520 

357 

0 

Oct. 

1     s 

1,309 

139 

0 

119,653 

2,800 

0 

0 

2,439 

236 

0 

Nov. 

1.352 

0 

0 

116,978 

2,870 

0 

0 

2.520 

0 

0 

Dec 
Total  or 

70,041 

15,922 

2,916 

0 

70,413 

84,954 

54.152 

29,672 

4,309 

0 

average 

392 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  13a  (Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL,  SEASONAL  AND 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  control  reserve  or 

first 

IQA 

131,000  acre-feet  of  capacity 

loiJ,uuu  auie- 

Flood 

Yield 

Flood 

control 

control 

Year  and 
month 

Run-off 

at 
.\zusa 

in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 

water 
passing 
Azusa 
during 

flood 
season 
at  rates 
less  than 

1,900 

Season- 
ally 
stored 
water  in 
acre-feet 

in  a 
uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

Passed 
by  Ham 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 

water 
passing 

.■\zu8a 
during 

flood 
season 
at  rates 
less  than 

1.900 

acre-feet 

second- 

acre-feet 

second- 

feet  in 
acre-feet 

in 
acre-feet 

feet  in 
acre-feet 

1912 

.Jan. 

2.710 

0 

2,710 

0 

0 

0 

0 

0 

51,321 

2,710 

0 

Feb. 

2.2.30 

0 

2,2^0 

0 

0 

0 

0 

0 

49.969 

2,230 

0 

Mar. 

22.900 

0 

8,199 

0 

0 

0 

0 

0 

48.704 

8.199 

0 

Anril 

18.000 

14,701 

8,515 

0 

2,314 

0 

95 

0 

62.053 

8.515 

0 

May 

10.900 

21,777 

8,828 

0 

4.273 

0 

163 

0 

69.991 

8,828 

0 

June 

4,990 

19,413 

4,990 

0 

4.634 

0 

182 

0 

69.228 

4,990 

0 

July 

3,060 

14,597 

3,060 

0 

4.790 

0 

184 

0 

65.940 

3.060 

0 

Aug. 

1,960 

9,623 

1,960 

0 

4,790 

0 

135 

0 

62,502 

1,960 

0 

S.pt. 

I,55t) 

4,698 

1,5.50 

0 

4,634 

0 

64 

0 

59,131 

1,550 

0 

Oct. 

1,830 

0 

1,830 

0 

0 

0 

0 

0 

55,864 

1,830 

0 

Nov, 

1,730 

0 

1,730 

0 

0 

0 

0 

0 

54,297 

1,730 

0 

Dee. 

1,760 

0 

1,760 

0 

0 

0 

0 

0 

52.849 

1.706 

0 

Total  or 

average 

73,620 

47.362 

0 

25,435 

0 

823 

0 

47.362 

0 

1913 

Jan. 

2,910 

0 

2,910 

0 

0 

0 

0 

0 

51.497 

2.910 

0 

Feb. 

13,200 

0 

4,753 

0 

0 

0 

0 

0 

50.145 

4.753 

0 

Mar. 

10,200 

8,447 

8,759 

0 

0 

0 

0 

0 

57.370 

8.759 

0 

April 

7,140 

9,888 

7,091 

0 

1,547 

0 

75 

0 

57.459 

7,091 

0 

May 

4,970 

8,315 

4,970 

0 

1,608 

0 

93 

0 

55.993 

4,970 

0 

June 

2,890 

6,614 

2,890 

0 

1.557 

0 

95 

0 

54,367 

2,890 

0 

July 

1,690 

4,962 

1,690 

0 

1.607 

0 

93 

0 

52,737 

1,690 

0 

Aug. 

1,070 

3,262 

1.070 

0 

1.607 

0 

68 

0 

51.010 

1,070 

0 

Sept. 

.893 

1,587 

893 

0 

1.555 

0 

32 

0 

49.318 

893 

I) 

Oct. 

910 

0 

910 

0 

0 

0 

0 

0 

47.749 

910 

0 

Nov. 

2,280 

0 

2.280 

0 

0 

0 

0 

0 

46,201 

2.280 

0 

Dec. 

2,170 

0 

2.170 

0 

0 

0 

0 

0 

44,765 

2,170 

0 

Total  or 

average 

50.323 

40,386 

0 

9.481 

0 

456 

0 

40.386 

I) 

1914 

Jan. 

01,400 

0 

6,271 

41,989 

0 

0 

0 

0 

43,413 

6,271 

35.050 

Feb. 

121,000 

13,140 

8.440 

59,505 

0 

0 

0 

0 

62.140 

8,440 

58,284 

Mar. 

48,000 

66,195 

9,344 

53,083 

0 

0 

0 

0 

115,194 

9,344 

52,388 

April 

21,400 

51.768 

9,042 

0 

8,291 

0 

193 

0 

100,110 

9,012 

0 

May 

16,900 

55.642 

9,344 

0 

11,077 

0 

274 

0 

105.206 

9..344 

0 

June 

9,580 

51,847 

8  585 

0 

12.509 

0 

313 

0 

102,701 

8,585 

0 

July 

5.570 

40,020 

5,570 

0 

13.258 

0 

317 

0 

92,040 

5.570 

0 

Aug. 

3,630 

26,445 

3.630 

0 

13.258 

0 

238 

0 

79,660 

3,630 

0 

Si-pt. 

2,730 

12,949 

2.730 

0 

12.826 

0 

123 

0 

67,426 

2,730 

0 

Oct. 

2.770 

0 

2,770 

0 

0 

0 

0 

0 

55,703 

2,770 

(I 

Nov. 

2,440 

0 

2.440 

0 

0 

0 

0 

0 

54,137 

2,440 

0 

Dec. 
Total  or 

4,290 

0 

4.290 

0 

0 

0 

0 

0 

52.689 

4.290 

0 

average 

299,710 

72,456 

154,577 

71,219 

0 

1,458 

0 

72,456 

145.722 

THE   CONTROL   OF    FLOODS   BY   RESERVOIRS. 


393 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

OVER- YEAR  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  13,  page  160.) 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000 

acre-feet  capacity 

Yield 

Flood 
control 

Yield 

in  a 

Passed 

water 

in  a 

Season- 

uni- 
formly 
con- 

Evapora- 
tion 

Waste 

Stage  of 
reservoir 

by  dam 
for  prior 
rights 
rfirst 152 
second- 
feet  of 
natural 
flow)  in 
acre-feet 

passing 
Azusa 

during 
flood 

season 

at  rates 

less  than 

1,900 

second- 

Season- 

uni- 
formly 
con- 

Evapora- 
tion 

Waste 

Year  and 

ally 
stored 
water  in 

tinuous 
supply 
from 

from 
reservoir 
surface 

over 
spill- 
way 

at  be- 
ginning 
of 

ally 
stored 
waterin 

tinuous 
supply 
from 

from 
reservoir 
surface 

over 
spill- 
way 

month 

acre-feet 

over- 
year 
storage 

in 
acre-feet 

in 
acre-feet 

month  in 
acre-feet 

acre-feet 

over- 
year 
storage 

in 
acre-feet 

in 
acre-feet 

in 

acre-feet 

feet  in 
acre-feet 

in 

acre-feet 

1912 

0 

1,352 

0 

0 

114,458 

2,710 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,265 

0 

0 

111,938 

2,230 

0 

0 

2,358 

0 

0 

Feb. 

0 

1,352 

0 

0 

109,580 

8,199 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

238 

0 

121,761 

8,515 

0 

0 

2,439 

337 

0 

April 

1,168 

1,352 

315 

0 

128,470 

8,828 

0 

0 

2,520 

473 

0 

May 

1,606 

1,309 

373 

0 

127,549 

4,990 

0 

0 

2,439 

565 

0 

June 

1,660 

1,352 

426 

0 

124,545 

3,060 

0 

0 

2,520 

656 

0 

July 

1,660 

1,352 

359 

0 

121,369 

1.960 

0 

0 

2,520 

602 

0 

Aug. 

1,667 

1,309 

291 

0 

118.247 

1,550 

0 

0 

2,439 

456 

0 

Sept. 

0 

1,352 

215 

0 

115,352 

1,830 

0 

0 

2,520 

343 

0 

Oct. 

0 

1,.309 

139 

0 

112,489 

1,7,30 

0 

0 

2,439 

226 

0 

Nov. 

0 

1,352 

0 

0 

109,824 

1,760 

0 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

7,761 

15,965 

2,356 

0 

47,362 

0 

0 

29,754 

3,658 

0 

1913 

0 

1,352 

0 

0 

107,304 

2,910 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

104,784 

4,753 

0 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

110,955 

8,759 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

206 

0 

109,876 

7,091 

0 

0 

2,439 

315 

0 

April 

0 

1,352 

274 

0 

107,171 

4,970 

0 

0 

2,520 

420 

0 

May 

0 

1,309 

321 

0 

104,231 

2,890 

0 

0 

2,439 

493 

0 

June 

0 

1,352 

375 

0 

101,299 

1,690 

0 

0 

2,520 

573 

0 

July 

0 

1352 

340 

0 

98,206 

1,070 

0 

0 

2,520 

523 

0 

Aug. 

0 

13M 

260 

0 

95,163 

893 

0 

0 

2,439 

394 

0 

Sept. 

0 

1352 

196 

0 

92,330 

910 

0 

0 

2,520 

297 

0 

Oct. 

-               0 

1,309 

127 

0 

89,513 

2,280 

0 

0 

2,439 

194 

0 

Nov. 

0 

1,352 

0 

0 

86,880 

2,170 

0 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

0 

15,922 

2,099 

0 

40,386 

0 

0 

2:1,672 

3,209 

0 

1914 

1    I 

1,352 

0 

0 

84,360 

6,271 

20,557 

0 

2,520 

0 

0 

Jan. 

1,222 

0 

0 

116,412 

8,440 

51,500 

0 

2,276 

0 

0 

Feb. 

1,352 

0 

0 

175,196 

9,344 

51,782 

0 

2,520 

0 

0 

Mar. 

5,652 

1,309 

301 

0 

159,550 

9,042 

0 

3,070 

2.439 

407 

0 

April 

8,299 

1,352 

410 

0 

165,992 

9,344 

0 

5,656 

2,520 

565 

0 

May 

9,875 

1,309 

472 

0 

164,807 

8,585 

0 

7,317 

2,439 

676 

0 

June 

10,512 

1,352 

516 

0 

155,370 

5,570 

0 

7,893 

2,520 

765 

0 

July 

10,450 

1,352 

432 

0 

144,192 

3,630 

0 

7,892 

2.520 

676 

0 

Aug. 

10,113 

1,309 

301 

0 

133,104 

2  730 

0 

7,639 

2,439 

496 

0 

Sept. 

0 

1,352 

214 

0 

122,530 

2,770 

0 

0 

2,520 

357 

0 

Oct. 

0 

1,309 

139 

0 

119,653 

2  440 

0 

0 

2,439 

236 

0 

Nov. 

0 

1,352 

0 

0 

116,978 

4,290 

0 

0 

2.520 

0 

0 

Dec. 
Total  or 
average 

54,901 

15  922 

2  785 

0 

72  456 

123,839 

39,467 

29,672 

4,178 

0 

25—52411 


394 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  13a  (Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL,  SEASONAL  AND 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  control  reserve  or 

first 

131,000  acre-feet  of  capacity 

IBO.uuu  acre- 

Flood 

Yield 

Flood 

control 

control 

Year  and 
month 

Run-off 

at 
Azusa 

in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 

water 

passing 

Azusa 

during 

flaod 

season 

at  rates 

less  than 

1,900 

Season- 
ally 
stored 
water  in 
acre-feet 

in  a 
uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights 
vfirst  152 
second- 
feet  of 
natural 
flow)  in 

water 
passing 

.\zusa 
during 

flood 

season 

at  rates 

less  than 

1,900 

acre-feet 

second- 

acre-feet 

second- 

feet  in 
acre-feet 

in 
acre-feet 

feet  in 
acre-feet 

1915 

Jan. 

7,380 

0 

4,428 

2,632 

0 

0 

0 

0 

51,337 

4,428 

3,029 

Feb. 

30,200 

320 

8.412 

13,196 

0 

0 

0 

0 

49,308 

8,412 

12,355 

Mar. 

21,500 

8,912 

9,344 

0 

0 

0 

0 

0 

57,519 

9,344 

0 

April 

17,300 

21,068 

9,042 

0 

3.339 

0 

117 

0 

68,323 

9,042 

0 

May 

20,400 

25,870 

9,344 

0 

4,256 

0 

177 

0 

74,618 

9,344 

0 

June 

11,400 

32,493 

8,967 

0 

7,807 

0 

238 

0 

81,891 

8,967 

0 

July 

7,010 

2fi,881 

7,010 

0 

8,875 

0 

254 

0 

77,842 

7.010 

0 

Aug. 

3,980 

17,752 

3,980 

0 

8,875 

0 

190 

0 

70,305 

3.980 

0 

Sept. 

3,270 

8,687 

3,270 

0 

8,592 

•   0 

95 

0 

62.829 

3.270 

0 

Oct. 

2,770 

0 

2,770 

0 

0 

0 

0 

0 

55,694 

2.770 

0 

Nov. 

3,010 

0 

3,010 

0 

0 

0 

0 

0 

54,128 

3,010 

0 

Dec. 

3,580 

0 

3,580 

0 

9 

0 

0 

0 

52,680 

3.580 

0 

Total  or 

average 

131,800 

73.157 

15,828 

41.744 

0 

1,071 

0 

73.157 

15,984 

1916 

Jan. 

148,000 

0 

8,759 

52,702 

0 

0 

0 

0 

51,328 

8.759 

51,935 

Feb.- 

39,400 

86,539 

8,741 

99.427 

0 

0 

0 

0 

137,282 

8.741 

99,779 

Mar. 

34,800 

17,771 

9,344 

18 

0 

0 

0 

0 

66,897 

9.344 

603 

April 

19,900 

43,209 

9,042 

0 

6,913 

0 

174 

0 

90,398 

9.042 

0 

May 

10,400 

40,980 

9,130 

0 

9,304 

0 

248 

0 

95,618 

9.130 

0 

June 

5,830 

38,698 

5,830 

0 

9,314 

0 

204 

0 

88,764 

5.830 

0 

July 

4,770 

29,120 

4,770 

0 

9,624 

0 

264 

0 

80,541 

4,770 

0 

Aug. 

3,570 

19,232 

3,570 

0 

9.624 

0 

198 

0 

72.070 

3.570 

0 

Sept. 

2,810 

9,410 

2,810 

0 

9.314 

0 

96 

0 

63,667 

2.810 

0 

Oct. 

7.010 

0 

6,473 

0 

0 

0 

0 

0 

55,638 

6.473 

0 

Nov. 

4,130 

537 

4,130 

0 

0 

0 

7 

0 

54,609 

4,130 

0 

Dec. 

13,000 

530 

5.253 

0 

0 

0 

0 

0 

53.169 

5,253 

0 

Total  or 

average 

294,220 

77.852 

152.147 

54.093 

0 

1.251 

0 

77.852 

152.317 

1917 

Jan. 

9,280 

8,877 

8,172 

9,467 

0 

0 

0 

0 

60,164 

8,172 

10,464 

Feb. 

13,200 

518 

7.551 

0 

0 

0 

0 

0 

49,456 

7.551 

0 

Mar. 

13,600 

6,167 

9.344 

0 

0 

0 

0 

0 

53.883 

9,344 

0 

April 

10,500 

10,423 

9,042 

0 

1,640 

0 

73 

0 

56,787 

9.042 

0 

May 

8,610 

10,168 

8,531 

0 

1,979 

0 

99 

0 

56,728 

8.531 

0 

June 

5,270 

8,169 

5,270 

0 

1,935 

0 

105 

0 

55,179 

5.270 

0 

July 

3,140 

6,129 

3,140 

0 

1,999 

0 

99 

0 

53.543 

3,140 

0 

Aug. 

2.200 

4,031 

2,200 

0 

1,999 

0 

67 

0 

51.812 

2,200 

0 

Sept. 

1,510 

1,965 

1.510 

0 

1,935 

0 

30 

0 

50.115 

1,510 

0 

Oct. 

1.560 

0 

1,560 

0 

0 

0 

0 

0 

48.514 

1.560 

0 

Nov. 

1,840 

0 

1,840 

0 

0 

0 

0 

0 

46,994 

1,840 

0 

Dec. 

2,000 

0 

2,000 

0 

0 

0 

0 

0 

45,558 

2,000 

0 

Total  or 

average 

72,710 

60,160 

9,467 

11.487 

0 

473 

0 

60.160 

10.464 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

OVER- YEAR  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  13,  page  160.) 


395 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  capacity 

240,000  acre-feet  capacity 

Flood 

Yield 

control 

Yield 

in  a 

Passed 

water 

in  a 

Season- 

ally 

stored 

water  in 

acre-feet 

uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

by  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 
acre-feet 

passing 
Azusa 
during 
flood 
season 
at  rates 
less  than 

1,900 
second- 
feet  in 
acre-feet 

Season- 
ally 
stored 
water  in 
acre-feet 

uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Year  and 
month 

1915 

0 

1,352 

0 

0 

114,458 

4,428 

5,570 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

109,320 

8,412 

11,720 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

117,112 

9,344 

0 

0 

2,520 

0 

0 

Mar. 

416 

1,309 

238 

0 

126,748 

9,042 

0 

0 

2,439 

353 

0 

April 

2,090 

1,352 

341 

0 

132,214 

9,344 

0 

0 

2,520 

494 

0 

May 

4,759 

1,309 

414 

0 

140,256 

8,967 

0 

1,326 

2,439 

603 

0 

Jime 

5,717 

1,352 

468 

0 

138,321 

7,010 

0 

2,189 

2,520 

706 

0 

July 

5,717 

1,352 

407 

0 

132,906 

3,980 

0 

2,188 

2,520 

640 

0 

.■^ug. 

5,533 

1,309 

293 

0 

127,558 

3,270 

0 

2,109 

2,439 

480 

0 

Sept 

0 

1,352 

214 

0 

122,530 

2,770 

0 

0 

2,520 

357 

0 

Oct. 

0 

1,309 

139 

0 

119,653 

3,010 

0 

0 

2,439 

236 

0 

Nov 

0 

1,352 

0 

0 

116,978 

3,580 

0 

0 

2,520 

0 

0 

Dec. 

Total  or 

24,232 

15,922 

t,514 

0 

73,157 

17,290 

7,812 

29,672 

3,869 

0 

average 
1916 

0 

1,352 

C 

0 

114,458 

8,759 

51,481 

0 

2,520 

0 

0 

Jan. 

0 

1,265 

0 

0 

199,698 

8,741 

99,327 

0 

2,358 

0 

0 

Feb. 

0 

1,352 

0 

0 

128,672 

9,344 

2,340 

0 

2,520 

0 

C 

Mar. 

4,045 

1,309 

284 

0 

149,268 

9,042 

0 

1,398 

2,439 

389 

0 

April 

6,393 

1,352 

379 

0 

155,900 

9,130 

0 

3,62o 

2,520 

541 

0 

May 

6,484 

1,309 

430 

0 

150,483 

5,830 

0 

3,819 

2,439 

633 

0 

June 

6,639 

1,352 

480 

0 

143,592 

4,770 

0 

3,946 

2,520 

724 

0 

July 

6,639 

1,352 

412 

0 

136,402 

3,570 

0 

3,945 

2,520 

650 

0 

Aug. 

6,425 

1,309 

295 

0 

129,287 

2,810 

0 

3,832 

2,439 

486 

0 

Sept. 

0 

1,352 

214 

0 

122,530 

6,473 

0 

0 

2,520 

357 

0 

Oct. 

0 

1,309 

131 

0 

120,190 

4,130 

0 

0 

2,439 

236 

0 

Nov. 

0 

1,352 

0 

0 

117,515 

5,253 

141 

0 

2,520 

0 

0 

Dec. 
Total  or 

36,625 

15.965 

2,625 

0 

77,852 

153,289 

20,566 

29,754 

4,016 

0 

average 
1917 

0 

1,352 

0 

0 

123,201 

8,172 

12,270 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

109,519 

7,551 

0 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

112,892 

9,344 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

208 

0 

114,628 

9,042 

0 

0 

2,439 

325 

0 

April 

0 

1,352 

276 

0 

113,322 

8,531 

0 

0 

2,520 

432 

0 

May 

0 

1,309 

327 

0 

110,449 

5,270 

0 

0 

2,439 

508 

0 

June 

0 

1,352 

379 

0 

107,502 

3,140 

0 

0 

2,520 

589 

0 

July 

0 

1,352 

345 

0 

104,393 

2,200 

0 

0 

2,520 

539 

0 

Aug. 

0 

1,309 

262 

0 

101,334 

1,510 

0 

0 

2,439 

408 

0 

Sept. 

0 

1,352 

198 

0 

98,487 

1,560 

0 

0 

2,520 

305 

0 

Oct. 

0 

1,309 

127 

0 

95,662 

1,840 

0 

0 

2,439 

202 

0 

Nov. 

0 

l,3.i2 

0 

0 

93,021 

2,000 

0 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

0 

15,922 

2,122 

0 

60,160 

12,270 

0 

29,672 

3,308 

0 

396 


WATER  RESOURCES  OP    CALIFORNIA, 


TABLE  13a  (Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL,  SEASONAL  AND 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  confro!  reserve  or 

first 

131,000 

icre-feet  of  capacity 

ISO.uuu  acie- 

Flood 

Yield 

Flood 

control 

control 

Year  and 
month 

Run-off 

at 
Azusa 

in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

Passed 
by  dan. 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 

water 

passing 

Azusa 

during 

flood 

season 

at  rates 

less  than 

1,900 

Season- 
ally 
stored 
water  in 
acre-feet 

m  a 
uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 

water 
passing 

Azusa 
during 

flood 

season 

at  rates 

les.<:  than 

1,900 

acre-feet 

second- 

acre-feet 

second- 

feet  in 

in 
acre-feet 

feet  in 

acre-feet 

acre-feet 

1918 

Jan. 

2,020 

0 

2,020 

0 

0 

0 

0 

0 

44.206 

2,020 

0 

Feb. 

9,330 

0 

3,847 

0 

0 

0 

0 

0 

42,854 

3,847 

0 

Mar. 

73.200 

5,483 

9,249 

11,341 

0 

0 

0 

0 

4/, 115 

9,249 

3,595 

.\pril 

17,000 

58,093 

9,042 

0 

9,314 

0 

206 

0 

106,119 

9,042 

0 

May 

10,000 

56,531 

8,993 

0 

11,216 

0 

276 

0 

105,858 

8,993 

0 

June 

6,010 

46,046 

6,010 

0 

11,097 

0 

292 

0 

96,679 

6.010 

0 

July 

3,970 

34,657 

3,970 

0 

11,167 

0 

293 

0 

86.528 

3.970 

0 

Aug. 

2,840 

22,897 

2,840 

0 

11,467 

0 

218 

0 

76,012 

2.840 

0 

Sept. 

2,330 

11,212 

2,330 

0 

11,099 

0 

113 

0 

65.632 

2.330 

0 

Oct. 

2,930 

0 

2,930 

0 

0 

0 

0 

0 

55.697 

2.930 

0 

Nov. 

3,140 

0 

3,140 

0 

0 

0 

0 

0 

54,131 

3.140 

0 

Dec. 

4,370 

0 

4,370 

0 

0 

0 

0 

0 

52,683 

4.370 

0 

Total  or 
average 

137,140 

58,741 

11,341 

65,660 

0 

1,398 

0 

58.741 

3,595 

1919 

Jan. 

3,300 

0 

3,300 

0 

0 

0 

0 

0 

51,331 

3,300 

0 

Feb. 

4,110 

0 

4,110 

0 

0 

0 

0 

0 

49.979 

4,110 

0 

Mar. 

6.110 

0 

6,110 

0 

0 

0 

0 

0 

48,757 

6,110 

0 

April 

6,010 

0 

6,010 

0 

0 

0 

0 

0 

47,405 

6.010 

0 

May 

3,810 

0 

3,810 

0 

0 

0 

0 

0 

45.914 

3,810 

0 

June 

1,890 

0 

1.890 

0 

0 

0 

0 

0 

44,318 

1,890 

0 

July 

1,320 

0 

1,320 

0 

0 

0 

0 

0 

42,725 

1.320 

0 

Aug 

935 

0 

935 

0 

0 

0 

0 

0 

41.044 

935 

0 

Sept. 

1,010 

0 

1,010 

0 

0 

0 

0 

0 

39,393 

1.010 

0 

Oct. 

2,040 

0 

2,040 

0 

0 

0 

0 

0 

37.854 

2.040 

0 

Nov. 

2,130 

0 

2.130 

0 

0 

0 

0 

0 

36,331 

2.130 

0 

Dec. 

5,340 

0 

5.209 

0 

0 

0 

0 

0 

34,913 

5.209 

0 

Total  or 
average 

38,005 

37.874 

0 

0 

0 

0 

0 

37.874 

0 

1920 

Jan. 

3,260 

131 

3,260 

0 

0 

0 

0 

0 

33,692 

3.260 

0 

Feb. 

12,700 

131 

5,854 

0 

0 

0 

0 

0 

32,340 

5.854 

0 

Mar. 

36.200 

6,977 

9,344 

0 

0 

0 

0 

0 

37,921 

9,344 

0 

April 

25,100 

33,833 

9,042 

0 

5.389 

0 

153 

0 

63,425 

9.042 

0 

May 

12,600 

44,349 

9.344 

0 

8.776 

0 

240 

0 

77,838 

9.344 

0 

June 

7,380 

38,589 

7.349 

0 

0,286 

0 

264 

c 

76,737 

7.349 

0 

July 

4,670 

29.070 

4.670 

0 

9,603 

0 

270 

0 

71, .554 

4,070 

0 

Aug. 

3,200 

19.197 

3,200 

0 

9,603 

0 

200 

0 

66,191 

3,200 

0 

Sept. 

2,030 

9,394 

2.030 

0 

9.292 

0 

102 

0 

60,817 

2,030 

0 

Oct. 

2,000 

0 

2.000 

0 

0 

0 

0 

0 

55,708 

2,000 

0 

Nov. 

2,380 

0 

2.380 

0 

0 

0 

0 

0 

54,142 

2.380 

0 

Dec. 

2,210 

0 

2.210 

0 

0 

0 

0 

0 

52,694 

2.210 

0 

Total  or 
average 

113.730 

60,683 

0 

51,949 

0 

1,229 

0 

60,683 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


397 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

OVER- YEAR  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  13,  page  160.) 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000 

acre-feet  capacity 

Flood 

Yield 

control 

Yield 

in  a 

Passed 

water 

in  a 

Season- 
ally 
stored 
water  in 
acre-feet 

uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

by  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 
acre-feet 

passing 
A^usa 
during 
flood 
season 
at  rates 

less  than 

1,900 
second- 
feet  in 

acre-feet 

Season- 
ally 
stored 
water  in 
acre-feet 

uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Year  and 
month 

1918 

0 

1,352 

0 

0 

90,501 

2,020 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

87,981 

3,847 

0 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

91,188 

9,249 

0 

0 

2,520 

0 

0 

Mar. 

6,603 

1,309 

307 

0 

152,619 

9,042 

0 

1,981 

2,439 

395 

0 

April 

8,422 

1,352 

412 

0 

155,762 

8,993 

0 

3,603 

2,520 

541 

0 

May 

8,388 

1,309 

454 

0 

150,105 

6,010 

0 

3,729 

2,439 

o33 

0 

June 

8,668 

1,352 

496 

0 

143,304 

3,970 

0 

3,854 

2,520 

724 

0 

July 

8,606 

1,352 

422 

0 

136,206 

2,840 

0 

3,854 

2,520 

650 

0 

Aug. 

8,329 

1,309 

297 

0 

129,182 

2,330 

0 

3,727 

2,439 

486 

0 

Sept. 

0 

1,352 

214 

0 

122,530 

2,930 

0 

0 

2,.520 

357 

0 

Oct. 

0 

1,309 

139 

0 

119,653 

3,140 

0 

0 

2,439 

230 

0 

Nov. 

0 

1,352 

0 

0 

116,978 

4,370 

0 

0 

2,520 

0 

0 

Dec. 

Total  or 
average 

49,016 

15,922 

2,741 

0 

58,741 

0 

20,748 

29,672 

4,022 

0 

1919 

0 

1,352 

0 

0 

114,458 

3,300 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

111,938 

4,110 

0 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

109,662 

6,110 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

182 

0 

107,142 

6,010 

0 

0 

2,439 

310 

0 

April 

0 

1,352 

244 

0 

104,393 

3,810 

0 

0 

2,520 

412 

0 

May 

0 

1,309 

284 

0 

101,461 

1,890 

0 

0 

2,439 

485 

0 

June 

0 

1,352 

329 

0 

98,537 

1,320 

0 

0 

2,520 

561 

0 

July 

0 

1,352 

299 

0 

95,456 

935 

0 

0 

2,520 

514 

0 

Aug. 

0 

1,309 

230 

0 

92,422 

1,010 

0 

0 

2,439 

387 

0 

Sept. 

0 

1,352 

171 

0 

89,590 

2,040 

0 

0 

2,520 

291 

0 

Oct. 

0 

1,309 

109 

0 

86,785 

2,130 

0 

0 

2,439 

190 

0 

Nov. 

0 

1,352 

0 

0 

84,156 

5,209 

0 

0 

2,520 

0 

0 

Doc. 
Total  or 
average 

0 

15,922 

1,818 

0 

37,874 

0 

0 

29,6.2 

3,150 

0 

1920 

0 

1,352 

0 

0 

81,767 

3,260 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,265 

0 

0 

79,247 

5,854 

0 

0 

2,358 

0 

0 

Feb. 

0 

1,-352 

0 

0 

83,735 

9.344 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

236 

0 

108,071 

9,042 

0 

0 

2,439 

311 

0 

April 

2,766 

1,352 

339 

0 

121.379 

9,344 

0 

0 

2,520 

462 

0 

May 

3,510 

1,309 

395 

0 

121,653 

7,349 

0 

0 

2,439 

547 

0 

June 

3,565 

1,352 

446 

0 

118,698 

4,670 

0 

0 

2,520 

635 

0 

July 

3,627 

1,352 

395 

0 

115,543 

3,200 

0 

0 

2,520 

581 

0 

Aug. 

3,510 

1,309 

290 

0 

112,442 

2,030 

0 

0 

2,439 

442 

0 

Sept. 

0 

1,352 

214 

0 

109,561 

2,000 

0 

0 

2,520 

331 

0 

Oct. 

0 

1,309 

139 

0 

106,710 

2,,380 

0 

0 

2,439 

218 

0 

Nov. 

0 

1,352 

0 

0 

104,053 

2,210 

0 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

16,978 

15,965 

2,454 

0 

60,683 

0 

0 

29.754 

3,527 

0 

398 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  13a  (Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL,  SEASONAL  AND 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  control 

reserve  or 

first 

1Qfl 

131,000  acre-feet  of  capacity 

1  oU.uiiu  am  v 

Flood 

Yield 

Flood 

control 

control 

Year  and 
month 

Run-off 

at 
Azusa 

in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 

water 
passing 

Azusa 
daring 

flood 

season 

at  rates 

less  than 

1.900 

Season- 
ally 
stored 
water  in 
acre-feet 

in  a 
uni- 
formly 
con- 
tinuous 
STjpply 
from 
over- 
year 
Storage 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 

water 
passing 
Azusa 
during 

flood 

season 

at  rates 

less  than 

1,900 

acre-feet 

second- 

acre-feet 

second 

feet  in 
acre-feet 

in 
acre-feet 

feet  in 
acre-feel 

1921 

Jan. 

5,160 

0 

4.405 

0 

0 

0 

0 

0 

51,342 

4.405 

0 

Feb. 

4.490 

755 

4,490 

0 

0 

0 

0 

0 

50,745 

4.490 

0 

Mar. 

15,400 

755 

7,288 

0 

0 

0 

0 

0 

49,523 

7.288 

0 

April 

6,070 

8,867 

6,070 

0 

1,386 

0 

67 

0 

56,283 

6.070 

0 

May 

15,700 

7.414 

6,835 

0 

1.432 

0 

85 

0 

54,770 

6,835 

0 

June 

8,9?0 

14.762 

7,920 

0 

3,510 

0 

155 

0 

62,002 

7.920 

0 

July 

3,830 

12.157 

3,830 

0 

3,978 

0 

169 

0 

61.399 

3.830 

0 

Aug. 

2,450 

8.010 

2.450 

0 

3.978 

0 

121 

0 

59.450 

2.450 

0 

Sept. 

1,840 

3.911 

1.840 

0 

3,859 

0 

52 

0 

57,536 

1.840 

0 

Oct. 

2,040 

0 

2.040 

0 

0 

0 

0 

0 

55.703 

2.040 

0 

Nov. 

1,800 

0 

1.800 

0 

0 

0 

0 

0 

54,137 

1,800 

0 

Dec. 

119,000 

0 

5.045 

38,907 

0 

0 

0 

0 

52,689 

5,045 

39,506 

Total  or 
average 

186,760 

54,013 

38.907 

18,143 

0 

649 

0 

54,013 

39.506 

1922 

Jan. 

62,100 

75,048 

9.344 

108.425 

0 

0 

0 

0 

125.786 

9,344 

107.332 

Feb. 

88,900 

19,379 

8.440 

83.060 

0 

0 

0 

0 

69.858 

8,440 

83.316 

Mar. 

47.800 

16,779 

9.344 

3.196 

0 

0 

0 

0 

65.780 

9.344 

2.882 

April 

31.400 

52.039 

9.042 

0 

8,334 

0 

192 

0 

100,002 

9,042 

0 

May 

24,700 

65.871 

9.344 

0 

13,084 

0 

303 

0 

115,088 

9,344 

0 

June 

14.400 

67.840 

9.042 

0 

16,400 

0 

373 

0 

118,319 

9.042 

0 

July 

9,100 

56.425 

8,576 

0 

18,735 

0 

392 

0 

108.104 

8,576 

0 

Aug. 

5,080 

37,822 

5,080 

0 

18.997 

0 

287 

0 

90.789 

5.080 

0 

Sept. 

3.290 

18,538 

3.290 

0 

18.385 

0 

153 

0 

72,867 

3,290 

0 

Oct. 

3.110 

0 

3.110 

0 

0 

0 

0 

0 

55.724 

3,110 

0 

Nov. 

5,310 

0 

4,519 

0 

0 

0 

0 

0 

54.158 

4.519 

0 

Dec. 

21,500 

791 

8.456 

0 

0 

0 

0 

0 

53.499 

8,456 

1.990 

Total  or 
average 

316,690 

87.587 

194,681 

93,935 

0 

1.700 

0 

87,587 

195.520 

1923 

Jan. 

7,130 

13.835 

6.968 

13.042 

0 

0 

0 

0 

63,201 

6,968 

12.056 

Feb. 

7,830 

955 

7,791 

0 

0 

0 

0 

0 

40.955 

7.791 

0 

Mar. 

7,320 

994 

7.320 

0 

0 

0 

0 

0 

48.772 

7.320 

0 

April 
May 

8.330 

994 

8.079 

0 

157 

0 

8 

0 

47.420 

8  079 

0 

5.480 

1,080 

5.480 

0 

210 

0 

12 

0 

46.180 

5,480 

0 

Juno 

3.700 

858 

3.700 

0 

204 

0 

12 

0 

44.584 

3,700 

0 

July 

2,420 

642 

2,420 

0 

212 

0 

8 

0 

42.987 

2,420 

0 

Aug. 

1,090 

422 

1.990 

0 

212 

0 

6 

0 

41.304 

1,990 

0 

Sept. 

1,750 

204 

1.750 

0 

204 

0 

0 

0 

39.653 

1.750 

0 

Oct. 

1.710 

0 

1.710 

0 

0 

0 

0 

0 

38.112 

1,710 

0 

Nov. 

1.900 

0 

1.960 

0 

0 

0 

0 

0 

36.589 

1,960 

0 

Dec. 
Total  or 
average 

2.130 

0 

2,130 

0 

0 

0 

0 

0 

35.169 

2,130 

0 

51.750 

51.298 

13.042 

1.190 

0 

46 

0 

51,298 

12.056 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

OVER- YEAR  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  13,  page  160.) 


399 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000 

acre-feet  capacity 

Yield 

• 

Flood 
control 

Yield 

in  a 

Passed 

water 

in  a 

Season- 
ally 
stored 
water  in 
acre-feet 

uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

Ly  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 
acre-feet 

passing 
Anisa 
during 
flood 
season 
at  rates 

less  than 

1,900 
second- 
feet  in 

acre-feet 

Season- 
ally 
stored 
waterin 
acre-feet 

uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

in 
acre-feet 

Evapora- 
tion 
from 
reservoir 
surface 

in 
acre-feet 

Waste 
oyer 
spill- 
way 
in 
acre-feet 

Year  and 
month 

1921 

0 

1,352 

0 

0 

101,533 

4,405 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

99,768 

4,490 

0 

0 

2.276 

0 

0 

Feb. 

0 

1,352 

0 

0 

97,492 

7,288 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

204 

0 

103,084 

6,070 

0 

0 

2,439 

301 

0 

April 

0 

1,352 

281 

0 

100,344 

6,835 

0 

0 

2,520 

403 

0 

May 

0 

1,309 

354 

0 

106,286 

7,920 

0 

0 

2,439 

500 

0 

June 

184 

1,352 

413 

0 

104,407 

3,830 

0 

0 

2,520 

583 

0 

July 

184 

1,352 

378 

0 

101,304 

2,450 

0 

0 

2,520 

533 

0 

Aug. 

238 

1,309 

286 

0 

98,251 

1,840 

0 

0 

2,439 

404 

0 

Sept. 

0 

1,352 

214 

0 

95,408 

2,040 

0 

0 

2,520 

303 

0 

Oct. 

0 

1,309 

139 

0 

92,585 

1,800 

0 

0 

2,439 

198 

0 

Nov. 

0 

1,352 

0 

0 

89,948 

5,045 

20,952 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

606 

15,922 

2,269 

0 

54,013 

20,952 

0 

29,672 

3,225 

0 

1922 

0 

1,352 

0 

0 

180,431 

9,344 

103,406 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

127,261 

8,440 

79,666 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

125,779 

9,344 

2,562 

0 

2,520 

0 

0 

Mar. 

5,652 

1,309 

311 

0 

159,153 

9,042 

0 

2,974 

2,439 

406 

0 

April 

10,327 

1,352 

446 

0 

175,692 

9,344 

0 

7,605 

2,520 

589 

0 

May 

13,742 

1,309 

522 

0 

180,334 

9,042 

0 

11,108 

2,439 

720 

0 

June 

15,922 

1,352 

565 

0 

171,425 

8,576 

0 

13,268 

2,.520 

821 

0 

July 

16,106 

1,352 

404 

0 

155,340 

5,080 

0 

13,533 

2,520 

712 

0 

Aug. 

15,527 

1,309 

307 

0 

138,575 

3,290 

0 

13,098 

2,439 

508 

0 

Sept. 

0 

1,352 

214 

0 

122,530 

3,110 

0 

0 

2,.520 

357 

0 

Oct. 

0 

1,309 

141 

0 

119,653 

4,519 

0 

0 

2,439 

236 

0 

Nov. 

0 

1,352 

0 

0 

117,769 

8,456 

5,092 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

77,276 

15,922 

2,970 

0 

87,587 

190,726 

61,586 

29,672 

4,349 

0 

1923 

0 

1.352 

0 

0 

123,201 

6,968 

10,928 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

109,915 

7,791 

0 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

107,678 

7,320 

0 

0 

2,520 

0 

0 

Mar. 

0 

1303 

182 

0 

105,1.58 

8.079 

0 

0 

2.439 

305 

0 

April 

0 

1,352 

244 

0 

102,665 

5,480 

0 

0 

2,520 

403 

0 

May 

0 

1,309 

288 

0 

99,742 

3,700 

0 

0 

2,439 

474 

0 

June 

0 

1,352 

331 

0 

96,829 

2  420 

0 

0 

2,520 

549 

0 

July 

0 

1,352 

299 

0 

93,760 

1,990 

0 

0 

2,520 

500 

0 

Aug. 

0 

1,309 

232 

0 

90,740 

1,750 

0 

0 

2,439 

379 

0 

Sept. 

0 

1,352 

171 

0 

87,922 

1,710 

0 

0 

2,520 

288 

0 

Oct. 

0 

1,309 

111 

0 

8.5,114 

1,960 

0 

0 

2,4.39 

186 

0 

Nov. 

0 

1,352 

0 

0 

82,489 

2,130 

0 

0 

2,520 

0 

0 

Dec. 
Tota  or 
average 

0 

15,922 

1,858 

0 

51,298 

10,928 

0 

29,672 

3,084 

0 

400 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  13a  (Continued).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL,  SEASONAL  AND 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  control  reserve  or 

first 

180,000  acre- 

131,000  3 

cre-f  eat  of  capacity 

Flood 

Yield 

• 

Flood 

control 

control 

Run-off 

at 
Azusa 

in 
acre-feet 

Passed 

water 

in  a 

Passed 

water 

Year  and 
month 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

by  dam 
for  prior 
rights 
rfirst  152 
second- 
feet  of 
natural 
flow)  in 

passing 
Azusa 

during 
flood 

season 

at  rates 

less  than 

1,900 

Season- 
ally 
stored 
water  in 
acre-feet 

uni- 
formly 
con- 
tinuous 
supply 
from 
over- 
year 
storage 

Evapora- 
tion 
froa 
reservoir 
surface 

in 
acre-feet 

Waste 
over 
spill- 
way 
in 
acre-feet 

Stage  of 
reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

by  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 

passing 
Azusa 
during 

flood 
season 
at  rates 
less  than 

1,900 

acre-feet 

second- 

acre-feet 

second- 

feet  in 

in 
acre-feet 

feet  in 

acre-feet 

acre-feet 

1924 

Jan. 

2,170 

0 

2,170 

0 

0 

0 

0 

0 

33,817 

2.170 

0 

Feb. 

1,790 

0 

1,790 

0 

0 

0 

0 

0 

32.465 

1,790 

0 

Mar. 

4.130 

0 

3,714 

0 

0 

0 

0 

0 

31,200 

3,714 

0 

.\pril 

6.190 

416 

6,190 

0 

59 

0 

8 

0 

30,264 

6,190 

0 

May 

3,650 

349 

3,650 

0 

61 

0 

10 

0 

28.814 

3,650 

0 

June 

1,660 

278 

1.660 

0 

59 

0 

10 

0 

27,276 

1,660 

0 

July 

1,000 

209 

1,000 

0 

61 

0 

12 

0 

25.753 

1,000 

0 

.\ug. 

756 

136 

756 

0 

61 

0 

10 

0 

24.153 

756 

0 

Sept. 

744 

65 

744 

0 

59 

0 

6 

0 

22.579 

744 

0 

Oct. 

873 

0 

873 

0 

0 

0 

0 

0 

21.103 

873 

0 

Nov. 

1,190 

0 

1,190 

0 

0 

0 

0 

0 

19,628 

1,190 

0 

Dec. 
Total  or 
average 

1,780 

0 

1,780 

0 

0 

0 

0 

0 

18,240 

1,780 

0 

25,933 

25,517 

0 

360 

0 

56 

0 

25,517 

0 

1925 

Jan. 

1,710 

0 

1,710 

0 

0 

0 

0 

0 

16,888 

1,710 

0 

Feb. 

1.620 

0 

1,620 

0 

0 

0 

0 

0 

15,536 

1,620 

0 

Mar. 

2,510 

0 

2,423 

0 

0 

0 

0 

0 

14,314 

2,423 

0 

April 

7,200 

87 

5,765 

0 

0 

0 

4 

0 

13,049 

5,765 

0 

May 

3,050 

1,518 

3,050 

0 

285 

0 

29 

0 

13,086 

3,050 

0 

June 

1,840 

1,204 

1,840 

0 

278 

0 

28 

0 

11,629 

1.840 

0 

July 

824 

898 

824 

0 

285 

0 

24 

0 

10,189 

824 

0 

Aug. 

621 

589 

621 

0 

285 

0 

16 

0 

8.696 

621 

0 

Sept. 

492 

288 

492 

0 

278 

0 

10 

0 

7,227 

492 

0 

Oct. 

873 

0 

873 

0 

0 

0 

0 

0 

5,837 

873 

0 

Nov. 

1,010 

0 

1,010 

0 

0 

0 

0 

0 

4,433 

1,010 

0 

Dec. 

1,650 

0 

1,650 

0 

0 

0 

0 

0 

3.096 

1,650 

0 

Total  or 
avemjc 

23,400 

21,878 

0 

1,411 

0 

111 

0 

21,878 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

OVER- YEAR  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  13,  page  IbO.) 


401 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000 

acre-feet  capacity 

Yield 

Flood 
control 

Yield 

in  a 

Passed 

water 

in  a 

uni- 

by dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 
acre-feet 

uni- 

Season- 

formly 
con- 

Evapora- 
tion 

Waste 

Stage  of 
reservoir 

passing 
Azusa 

during 
flood 

season 

at  rates 

less  than 

1,900 

second- 

Season- 

formly 
con- 

Evapora- 
tion 

Waste 

Year  and 
month 

ally 

tinuous 

from 

over 
spill- 
way 

at  be- 

ally 

tinuous 

from 

over 
spill- 
way 

stored 
water  in 

supply 
from 

reservoir 
siirface 

ginning 
of 

stored 
water  in 

supply 
from 

reservoir 
surface 

acre-feet 

over- 
year 
storage 

in 
acre-feet 

in 
acre-feet 

month  in 
acre-feet 

acre-feet 

over- 
year 
storage 

in 
acre-feet 

in 
acre-feet 

in 

acre-feet 

feet  in 
acre-feet 

in 
acre-feet 

1924 

0 

1,352 

0 

0 

79,969 

2,170 

0 

0 

2.520 

0 

0 

Jan. 

0 

1,265 

0 

0 

77.449 

1,790 

0 

0 

2.358 

0 

0 

Feb. 

0 

1,352 

0 

0 

75,091 

3,714 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

141 

0 

72,987 

6,190 

0 

0 

2,439 

238 

0 

April 

0 

1,352 

186 

0 

70,310 

3,650 

0 

0 

2,520 

315 

0 

May 

0 

1,309 

214 

0 

67,475 

1.660 

0 

0 

2,439 

369 

0 

June 

0 

1,352 

248 

0 

64,667 

1,000 

0 

0 

2,520 

426 

0 

July 

0 

1,352 

222 

0 

61,721 

756 

0 

0 

2,520 

385 

0 

Aug. 

0 

1,309 

167 

0 

58.816 

744 

0 

0 

2,439 

290 

0 

Sept. 

0 

1,352 

123 

0 

56.087 

873 

0 

0 

2,520 

214 

0 

Oct. 

0 

1,309 

79 

0 

53.353 

1,190 

0 

0 

2.439 

139 

0 

Nov. 

0 

1,352 

0 

0 

50,775 

1,780 

0 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

0 

15,965 

1,380 

0 

25,517 

0 

0 

29,754 

2,376 

0 

1923 

0 

1,352 

0 

0 

48,255 

1,710 

0 

0 

2.520 

0 

0 

Jan. 

0 

1,222 

0 

0 

45,735 

1,620 

0 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

43,459 

2,423 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

89 

0 

41,026 

5,765 

0 

0 

2,439 

171 

0 

.\pril 

0 

1,352 

105 

0 

39.851 

3,050 

0 

0 

2,520 

222 

0 

May 

0 

1,309 

131 

0 

37,109 

1,840 

0 

0 

2,439 

254 

0 

June 

0 

1,352 

141 

0 

34,416 

824 

0 

0 

2,520 

288 

0 

July 

0 

1,352 

117 

0 

31,608 

621 

0 

0 

2,520 

256 

0 

Aug. 

0 

1,309 

81 

0 

28.832 

402 

0 

0 

2.439 

188 

0 

Sept. 

0 

1.352 

52 

0 

26.205 

873 

0 

0 

2.520 

137 

0 

Oct. 

0 

1,309 

28 

0 

23,548 

1,010 

0 

0 

2,439 

85 

0 

Nov. 

0 

1,352 

0 

0 

21,024 

1,650 

0 

0 

2,520 

0 

0 

D?c. 
Total  or 

avcragi^ 

0 

15,922 

744 

0 

21,878 

0 

0 

29,672 

1,601 

0 

402 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  13a  (Concluded).     SAN  GABRIEL 

WATER  YIELD  UNDER 

FLOOD  CONTROL,  SEASONAL  AND 
Monthly  Summary  of  Compute 

(For  corresponding  yearly  sum 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 
Reservoir  emptied  of  seas 


Maximum  flood  control  reserve  or 

first 

180,000  acre- 

131,000  acre-feet  of  capacity 

Flood 

Yield 

Flood 

control 

control 

Run-off 

Passed 

water 

in  a 

Passed 

water 

Year  and 

at 

Azusa 

in 

ace-feet 

Stapeof 

liy  dam 
for  prior 

passing 
Azusa 

Season- 
ally 

stored 

formly 

Evapora- 

Waste 

Stage  of 

by  dam 

for  prior 

passing 
Azusa 

month 

reservoir 
at  be- 
ginning 

riahts 
(first  152 
secord- 

during 
flood 
season 

con- 
tinuous 
supply 

tion 

from 

reservoir 

over 
spill- 
way 

reservoir 
at  be- 
ginning 

of 
month  in 
acre-feet 

rights 
(first  152 
second- 

during 
flood 
season 

of 
month  in 
acre-feet 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1,900 

water  in 
acre-feet 

from 
over- 
year 
storage 

surface 

in 
acre-feet 

in 
acre-feet 

feet  of 
natural 
flow)  in 

at  rates 

less  than 

1,900 

acre-feet 

second- 

acre-feet 

second- 

feet  in 
acre-feet 

in 
acre-feet 

feet  in 
acre-feet 

1926 

Jan. 

1,540 

0 

1,540 

0 

0 

0 

0 

0 

1,744 

1,540 

0 

Feb. 

7,i)40 

0 

5,485 

0 

0 

0 

0 

0 

392 

5,485 

0 

Mar. 

s.e.w 

2.455 

3,650 

0 

0 

0 

0 

0 

1,G25 

3.650 

0 

April 

00,000 

2,455 

8,233 

0 

383 

0 

32 

0 

273 

8.233 

0 

May 

13  000 

62,807 

9,142 

0 

12,471 

0 

294 

0 

59.572 

9,142 

0 

June 

5,500 

53,900 

5,500 

0 

13,006 

0 

323 

0 

61,785 

5,500 

0 

July 

3.120 

40,571 

3,120 

0 

13,441 

0 

321 

0 

60,127 

3.120 

0 

Aug. 

2,070 

2(i,809 

2,070 

0 

13,441 

0 

239 

0 

58,367 

2,070 

0 

Sept. 

1,580 

13,129 

1,580 

0 

13,001 

0 

128 

0 

56,642 

1,580 

0 

Oct. 

0 

0 

55.049 

0 

Nov. 

Dec. 

Total  or 
average 

107,400 

40,320 

0 

65,743 

0 

1.337 

0 

40,320 

0 

Total  for 

period, 

Jan.1, 

1897,  to 

Oct.l, 

1926 

3.731,977 

1,513,303 

1,103,359 

1,091,252 

0 

24,063 

0 

1,513,303 

•1,010.662 

Average 

for 

period, 

Jan.1, 

1897,  to 

Oct.l, 

1926 

125,445 

50,867 

37,088 

36,681 

0 

809 

0 

50,867 

■'33.972 

"  Those  figures  contain  7601  acre-feet  total  or  an  average  of  256  acre-feet  per  season  of  water  contributed  from  outside 
the  exact  period  of  analysis.  In  the  eominitat  inns  from  which  this  table  is  prepared,  the  water  in  storage  on  Octoler  1,  1926, 
the  end  of  the  period,  is  less  by  this  amount  than  on  January  I,  1897,  the  beginning  of  the  porinii.  i^inee  in  the  computations. 
this  water  was  released  as  flood  control  water  during  the  first  flood  season  of  tlieperio<l,  the  exact  yield  of  flood  control  water 
for  the  period  is  less  than  here  shown  by  this  amount. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

"COORDINATED  PLAN." 

OVER- YEAR  STORAGE  COORDINATED, 
tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  13,  page  160.) 


403 


Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights, 
onal  storage  each  year. 


feet  capacity 

240,000 

acre-feet  capacity 

Yield 

Flood 
control 

Yield 

in  a 

Passed 

water 

Season- 
ally 
stored 
water  in 

uni- 
formly 

con- 
tinuous 
supply 

from 

Evapora- 
tion 
from 
reservoir 
surface 

Waste 
over 
spill- 
way 

Stage  of 
reservoir 
at  bo- 
ginning 
of 

by  dam 
for  prior 
rights 
(first  152 
second- 
feet  of 
natural 
flow)  in 
acre-feet 

passing 
.A.zusa 

during 
flood 

season 

at  rates 

less  than 

1,900 

second- 

Season- 
ally 
stored 
water  in 

formly 

con- 

tinjous 

s.ipply 

from 

Evapora- 
tion 
from 
reservoir 
surface 

Waste 
over 
spill- 
way 

Year  and 
month 

acre-feet 

over- 
year 
storage 

in 
acre-feet 

acre-feet 

month  in 
acre-feet 

acre-feet 

over- 
year 
storage 

in 

acre-feet 

acre-feet 

acre-feet 

feet  in 
acre-feet 

acre-feet 

1926 

0 

1,352 

0 

0 

18,504 

1,540 

0 

0 

2,520 

0 

0 

Jan. 

0 

1,222 

0 

0 

15,984 

5,485 

0 

0 

2,276 

0 

0 

Feb. 

0 

1,352 

0 

0 

16,163 

3,650 

0 

0 

2,520 

0 

0 

Mar. 

0 

1,309 

159 

0 

13,643 

8,233 

0 

0 

2,439 

196 

0 

April 

0 

1,352 

293 

0 

71,775 

9,142 

0 

0 

2,520 

325 

0 

May 

0 

1,309 

349 

0 

72,788 

5,500 

0 

0 

2,439 

385 

0 

June 

0 

1,352 

408 

0 

69,964 

3,120 

0 

0 

2,520 

442 

0 

July 

0 

1,352 

373 

0 

67,002 

2,070 

0 

0 

2,520 

403 

0 

Aug. 

0 

1,309 

284 

0 

64,079 

1,580 

0 

0 

2,4.39 

303 

0 

Sept. 

0 

61,337 

0 

0 

0 

Oct. 

Nov. 

Dec. 
Total  or 
average 

0 

11,909 

1,866 

0 

40,320 

0 

0 

22,193 

2,054 

0 

Total  for 

period. 

Jan.1, 

1897,  to 

Oct.1, 

676,322 

473,905 

65,386 

0 

1,513,303 

891,925 

410,812 

883,173 

94,077 

0 

1928 

Average 

for 

period, 

Jan.1, 

1897.  to 

Oct.1, 

22,734 

15,930 

2,198 

0 

50,867 

b29,981 

1-13,809 

t'29,686 

3.162 

0 

1926 

•>  These  figures  contain  61,313  acre-feet  total  or  an  average  of  2060  aore-feet  per  season  of  water  contributed  from  outside 
the  exact  period  of  analysis.  In  the  computations  from  which  this  (able  is  prepared,  the  water  in  storage  on  October  1,  1926, 
the  end  of  the  period,  is  less  by  this  amount  than  on  .January  1,  1?97,  the  beginning  of  the  period.  A  supplementary  analj'sis, 
havingthesaraeamountof  wa  tor  in  storage  at  the  beginning  and  at  the  end  of  the  period,  was  made  to  obtain  the  exact  yield  for 
the  period.  This  gave  22,200,  25,900  and  23,300  acre-feet  perseason,  respectively,  for  the  flood  control  water  seasonally  stored 
water,  and  uniformly  continuous  flow  instead  of  29,981,  13,809,  and  29,686  acre-feet,  respectively,  that  are  shown  herein. 


404 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  15a.     SAN  GABRIEL  RESER 

COMPARISON  OF  WATER  YIELD  FOR 

COORDINATED  WITH  SEASONAL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Flood  control  by 

reservoir  operating  diagram 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  22  second-feet  maintained,  othe 

drafts  only 

as  required  by  reservoir  operating  diagram 

Flood 

Year  and 
month 

Run-off 

at  Azusa 

in  acre-feet 

Stage  of 
reservoir 

at 
beginning 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

control 
water 

passing 

Aziisa 

during 

flood  season 

at  rates 

less  than 

Constant 

draft 
from  over- 
year storage 
(?2  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reser\'oir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

1, 900  second- 

feet  in 

acre-feet 

1897 

Jan. 

3,617 

62,650 

3,617 

11779 

1.352 

0 

0 

0 

Feb. 

19,146 

49,519 

7.262 

4,628 

1.222 

0 

0 

0 

Mar. 

28,623 

55,553 

9,344 

0 

1.352 

0 

0 

0 

April 

17,519 

73.480 

9,042 

0 

1,309 

1,249 

234 

0 

May 

8.851 

79,165 

8,126 

0 

1,352 

3,012 

343 

0 

June 

4,033 

75,183 

4,033 

0 

1.309 

3,093 

396 

0 

July 

2,343 

70,385 

2,343 

0 

1.352 

3,197 

447 

0 

Aug. 

1.613 

65,389 

1.613 

0 

1.352 

3,197 

393 

0 

Sept. 

1.226 

60,447 

1,226 

0 

1.309 

3,153 

290 

0 

Oct. 

5,564 

55,(i95 

2,622 

0 

1.35? 

0 

220 

0 

Nov. 

1,860 

57,0,i5 

1,860 

0 

1,309 

0 

143 

0 

Dec. 
Total  or 
average 

1,875 

55,613 

1.875 

0 

1,352 

0 

0 

0 

96,270 

52,963 

16.407 

15,922 

16.901 

2.466 

0 

1898 

Jan. 

2,4.53 

.54,261 

2,453 

0 

1,352 

0 

0 

0 

Feb. 

2,241 

52,909 

2,241 

0 

1,222 

0 

0 

0 

Mar. 

2,131 

51,687 

2,131 

0 

1,352 

0 

0 

0 

April 

1,050 

50,335 

1,950 

0 

1,309 

0 

190 

0 

May 

2,213 

48,836 

2,213 

0 

1352 

0 

252 

0 

June 

1,150 

47,23? 

1,159 

0 

1,309 

0 

296 

0 

July 

672 

45.627 

672 

0 

1,352 

0 

343 

0 

Aug. 

456 

43,932 

456 

0 

1,3.52 

0 

313 

0 

Sept. 

467 

42.267 

467 

0 

1,309 

0 

238 

0 

Oct. 

533 

40.720 

533 

0 

1,352 

0 

179 

0 

Nov. 

580 

39,189 

580 

0 

1,309 

0 

115 

0 

Dec. 
Tobl  or 
average 

832 

37.765 

832 

0 

1,352 

0 

0 

0 

15.687 

15.687 

0 

15,922 

0 

1.926 

1899 

.Ian. 

1,414 

36,413 

1.414 

0 

1,3.52 

0 

0 

0 

Fell. 

1,244 

35,061 

1.244 

0 

1,222 

0 

0 

0 

Mar. 

1,623 

33.839 

1,623 

0 

1.352 

0 

0 

0 

April 

r,262 

32,487 

1,262 

0 

1.309 

0 

149 

0 

May 

842 

31.029 

842 

0 

1.352 

0 

194 

0 

June 

565 

29.483 

565 

0 

1.309 

0 

224 

0 

July 

221 

27.950 

221 

0 

1,352 

0 

260 

0 

Aug. 

295 

26,338 

295 

0 

1,352 

0 

234 

0 

Sept 

220 

24.752 

220 

0 

1,3P9 

0 

175 

0 

Oct. 

683 

23,268 

683 

0 

1.352 

0 

129 

0 

Nov. 

847 

21,787 

847 

0 

1.309 

0 

83 

0 

Dec. 
Total  or 
average 

1.247 

20,395 

1,247 

0 

1.352 

0 

0 

0 

10.463 

10.463 

0 

15,922  1                   0 

1.448 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


405 


VOIR  ON  SAN  GABRIEL  RIVER. 

TWO  METHODS  OF  FLOOD  CONTROL 
AND  OVER- YEAR  STORAGE, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  15,  page  180.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131.000  acre-feet. 
Reservoir  emptied  of  seasonal  storage  each  year. 


Flood  control,  holding  maximum  reservoir  space  required  (131,000  acre-feet)  in  reserve 

throughout  flood  season 

Reservoir  emptied  each 

Slimmer  to  a  level  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  18  second-feet  maintained,  other  drafts  only 

as  required  by  reservoir  operating  diagram 

Flood 

Stage  of 
reservoir 

at 
beginning 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

control 
water 
passing 
Azusa 
during 
flood  season 
at  rates 
less  than 

Constant 

draft 
from  over- 
year storage 
(18  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reseri-oir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

Year  and 
month 

1,900  second- 

feet  in 

acre-feet 

1897 

49,122 

3,617 

0 

1,107 

0 

0 

0 

Jan. 

48,015 

7,262 

9,778 

999 

0 

0 

0 

Feb. 

49.122 

9,344 

18,172 

1,107 

0 

0 

0 

Mar. 

49,122 

9,042 

5,983 

1,071 

0 

188 

0 

April 

50,357 

8,126 

0 

1,107 

0 

260 

0 

Maj 

49,715 

4,033 

0 

1,071 

0 

305 

0 

June 

48.339 

2,343 

0 

1,107 

0 

357 

0 

July 

46,875 

1,613 

0 

1,107* 

0 

329 

0 

Aug. 

45,439 

1,226 

0 

1,071 

0 

250 

0 

Sept. 

44,118 

2,622 

0 

1,107 

0 

190 

0 

Oct. 

45,763 

1,860 

0 

1,071 

0 

127 

0 

Nov. 

44,565 

1,875 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

52,963 

33,933 

13,032 

0 

2,006 

0 

1898 

43,458 

2,453 

0 

1,107 

0 

0 

0 

Jan. 

42,351 

2,241 

0 

999 

0 

0 

0 

Feb. 

41,352 

2,131 

0 

1,107 

0 

0 

0 

Mar. 

40,245 

1,950 

0 

1,071 

0 

165 

0 

April 

39,00" 

2,213 

0 

1,107 

0 

222 

0 

May 

37,680 

1,159 

0 

1,071 

0 

260 

0 

June 

36,349 

672 

0 

1,107 

0 

299 

0 

July 

34,943 

456 

0 

1,107 

0 

274 

0 

Aug. 

33,562 

467 

0 

1,071 

0 

210 

0 

Sept. 

32,281 

533 

0 

1,107 

0 

157 

0 

Oct. 

31,017 

580 

0 

1,071 

0 

101 

0 

Nov. 

29,845 

832 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

15.687 

0 

13,032 

0 

1,688 

0 

1899 

28,738 

1,414 

0 

1,107 

0 

0 

0 

Jan. 

27,631 

1,244 

0 

999 

0 

0 

0 

Feb. 

26,632 

1,623 

0 

1,107 

0 

0 

0 

Mar. 

25,525 

1,262 

0 

1,071 

0 

129 

0 

April 

24,325 

842 

0 

1.107 

0 

171 

0 

May 

23,047 

565 

0 

1.071 

0 

196 

0 

June 

21,780 

221 

0 

1,107 

0 

226 

0 

July 

20,447 

295 

0 

1,107 

0 

204 

0 

Aug. 

19,136 

220 

0 

1,071 

n 

153 

0 

Sept. 

17,912 

683 

0 

1,107 

0 

113 

0 

Oct. 

16,692 

847 

0 

1.071 

0 

71 

0 

Nov. 

15,550 

1,247 

0 

1.107 

0 

0 

0 

Dec. 

Total  or 
average 

10,463 

0 

13,032 

0 

1,263 

0 

406 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  15a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

COORDINATED  WITH  SEASONAL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Flood  control  by 

reservoir  operating  diagram 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant  draft  through  critica 

period;  constant  draft  of  22 

3econd-feet  maintained,  other  drafts  only 

as  required  by 

reservoir  operating  diagram 

Flood 

Year  and 
month 

Run-off 

at  Azusa 

in  acre-feet 

Stage  of 
reservoir 

at 
beginning 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

control 
water 
passing 
Azusa 
during 
flood  season 
at  rates 
less  than 

Constant 

draft 
from  over- 
year storage 
{22  second- 
feet)  in 
acre-feet 

Seasonally 

stored 

water  in 

acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

1,900  second- 

feet  in 

acre-feet 

1900 

Jan. 

1.968 

19,043 

1,968 

0 

1,352 

0 

0 

0 

Feb. 

1,111 

17,691 

1,111 

0 

1,222 

0 

0 

0 

Mar. 

1,230 

16,469 

1,230 

0 

1,352 

0 

0 

0 

April 

1,012 

15,117 

1,012 

0 

1,309 

0 

95 

0 

May 

2,275 

13,713 

2,275 

0 

1.352 

0 

121 

0 

June 

893 

12,240 

893 

0 

1,309 

0 

135 

0 

July 

309 

10,796 

369 

0 

1,352 

0 

149 

0 

Aug. 

246 

9,295 

246 

0 

1,352 

0 

123 

0 

Sept. 

238 

7,820 

238 

0 

1,309 

0 

85 

0 

Oct. 

307 

6,426 

307 

0 

1,352 

0 

56 

0 

Nov. 

11,068 

5,018 

1,058 

0 

1,309 

0 

32 

0 

Dec. 

1,269 

13,687 

1,269 

0 

1,352 

0 

0 

0 

Total  or 

average 

21,986 

11,976 

0 

15,922 

0 

796 

0 

1901 

Jan. 

10,391 

12,.335 

6,061 

0 

1,352 

0 

0 

0 

Feb. 

38,709 

14,713 

8,350 

0 

1,222 

0 

0 

0 

Mar. 

13,589 

43,850 

9,138 

0 

1,352 

0 

0 

0 

April 

6,545 

46,^49 

6,545 

0 

1,300 

0 

181 

0 

May 

7,440 

45,459 

6,990 

0 

1,352 

0 

?40 

0 

June 

3,749 

44,317 

3,749 

0 

1,309 

0 

286 

0 

July 

1,845 

42,722 

1,845 

0 

1,352 

0 

329 

0 

Aiig. 

1.240 

41,041 

1,240 

0 

1,352 

0 

300 

0 

Sept. 

1,012 

39.389 

1,012 

0 

1,309 

0 

230 

0 

Oct. 

1,476 

37,850 

1,476 

0 

1,352 

0 

171 

0 

Nov. 

1,904 

36,327 

1,904 

0 

1,309 

0 

109 

0 

Dec. 

1,860 

34,909 

1.'560 

0 

1,352 

0 

0 

0 

Total  or 

average 

89,560 

50,570 

0 

15,922 

0 

1,846 

0 

1902 

Jan. 

1,722 

33,557 

1,722 

0 

1.352 

0 

0 

0 

Feb. 

2,055 

32,206 

2,055 

0 

1.222 

0 

0 

0 

Mar. 

6,088 

30,983 

5,590 

0 

1,352 

0 

0 

0 

April 

3.928 

30,129 

3,928 

0 

1,309 

0 

141 

0 

May 

2,308 

28,679 

2,398 

0 

1,352 

0 

184 

0 

June 

I.IOO 

27,143 

1,190 

0 

1,309 

0 

214 

0 

July 

676 

25,620 

676 

0 

1,352 

0 

246 

0 

Aug. 

430 

24,022 

430 

0 

1,352 

0 

222 

0 

Sept. 

298 

22,448 

298 

0 

1,309 

0 

167 

0 

Oct. 

430 

20,972 

430 

0 

1,352 

0 

123 

0 

Nov. 

1,131 

19,497 

1,131 

0 

l,30f 

0 

77 

0 

Dec. 

1.968 

18,111 

1.968 

0 

1,352 

0 

0 

0 

Total  or 
average 

22.314 

21.816 

0 

16.922 

0 

1,374 

0 

THE    CONTROL    OF    FLOODS   BY    RESERVOIRS. 


407 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  METHODS  OF  FLOOD  CONTROL 
AND  OVER- YEAR  STORAGE 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  15,  page  180.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 
Reservoir  emptied  of  seasonal  storage  each  year. 


Flood  control,  holding  maximum  reservoir  space  required  (131,000  acre-feet)  in  reserve 
throughout  flood  season 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  18  second-feet  maintained,  other  drafts  only 

as  required  by  reservoir  operating  diagram 


Flood 

Stage  of 
reservoir 

at  _ 
beginning 
of  month 
in  acre-feet 

control 
water 

Constant 

Year  and 
month 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

passing 
Azusa 
during 
flood  season 
at  rates 
less  than 

draft 
from  over- 
year storage 
(18  second- 
feet)  in 
acre-feet 

Seasonally 
ptored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

ove'' 

spillway 

in  acre-feet 

1.900  second- 

feet  in 

acre-feet 

1900 

14,443 

1,968 

0 

1,107 

0 

0 

0 

Jan. 

13,336 

1,111 

0 

999 

0 

0 

0 

Feb. 

12,337 

1,230 

0 

1,107 

0 

0 

0 

Mar. 

11,230 

1,012 

0 

1,071 

0 

77 

0 

April 

10,082 

2,275 

0 

1.107 

0 

99 

0 

May 

8.876 

893 

0 

1,071 

0 

113 

0 

June 

7,092 

369 

0 

1,107 

0 

121 

0 

July 

6,464 

246 

0 

1,107 

0 

95 

0 

Aug. 

■  5,262 

238 

0 

1,071 

0 

63 

0 

Sept. 

4,128 

307 

0 

1,107 

0 

40 

0 

Oct. 

2,981 

1,058 

0 

1,071 

0 

36 

0 

Nov 

11.884 

1.269 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

11,976 

0 

13,032 

0 

644 

0 

1901 

10,777 

6,661 

0 

1,107 

0 

0 

0 

Jan. 

13,400 

8,350 

0 

999 

0 

0 

0 

Feb. 

42,760 

9,138 

0 

1,107 

0 

0 

0 

Mar. 

46,104 

6.545 

0 

1.071 

0 

178 

0 

April 

44,855 

6,990 

0 

1,107 

0 

246 

0 

May 

43,952 

3,749 

0 

1,071 

0 

284 

0 

June 

42,597 

1,845 

0 

1,107 

0 

329 

0 

July 

41,161 

1,240 

0 

1,107 

0 

301 

0 

Aug. 

39,753 

1,012 

0 

1,071 

0 

232 

0 

Sept. 

38,450 

1,476 

0 

1,107 

0 

173 

0 

Oct. 

37,170 

1,904 

0 

1,071 

0 

111 

c 

Nov. 

35,988 

1,660 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

50,570 

0 

13.032 

0 

1,854 

0 

1902 

34,881 

1,722 

0 

1,107 

0 

0 

0 

Jan. 

.33,774 

2,055 

0 

999 

0 

0 

0 

Feb. 

32,775 

5,590 

0 

1,107 

0 

0 

0 

Mar. 

32,166 

3,928 

0 

1,071 

0 

147 

0 

April 

30,948 

2,398 

0 

1,107 

0 

194 

0 

May 

29,647 

1,190 

0 

1,071 

0 

226 

0 

June 

28,350 

676 

0 

1,107 

0 

262 

0 

July 

26,981 

430 

0 

1,107 

0 

238 

0 

Aug. 

25,636 

298 

0 

1,071 

0 

178 

0 

Sept. 

24,387 

430 

0 

1,107 

0 

133 

0 

Oct. 

23,147 

1,131 

0 

1,071 

0 

85 

0 

Nov. 

21,991 

1,968 

0 

1,107 

0 

0 

0 

Dec. 

Total  or 
average 

21,816 

0 

13,032 

0 

1,463 

0 

408 


WATER  RESOURCES   OF   CALIFORNIA. 


TABLE  15a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

COORDINATED  WITH  SEASONAL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Flood  control  by 

reservoir  operating  diagram 

Reservoir  emptied  each  summer  to  a  leve 

1  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  22  second- feet  maintained,  other  drafts  only 

as  required  by  reservoir  operating  diagram 

Flood 

Year  and 
month 

Run-off 
at  Azusa 
in  acre-feet 

Stage  of 
reservoir 

at 
beginning 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

control 
water 
passing 
Azusa 
during 
flood  season 
at  rates 
leas  than 

Constant 

draft 
from  over- 
year storage 
(22  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reser\'oir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

l,900second- 

feet  in 

acre-feet 

1903 

Jan. 

9,100 

16,759 

2,536 

0 

1,352 

0 

0 

0 

Feb. 

5,665 

21,971 

5,497 

0 

1,222 

0 

0 

0 

Mar. 

15,802 

20,917 

7,898 

0 

1,352 

0 

0 

0 

April 

47,127 

27,469 

9,042 

0 

1,309 

0 

180 

0 

May 

13,343 

64,065 

9,116 

0 

1,352 

0 

307 

0 

June 

5,653 

66,633 

5,653 

0 

1,309 

1,012 

365 

0 

July 

2,644 

63,947 

2,644 

0 

1,352 

1.107 

421 

0 

Aug. 

1,783 

61,067 

1,783 

0 

1,352 

1.045 

379 

.    0 

Sept. 

1,488 

58,291 

1,488 

0 

1,309 

1.071 

288 

C 

Oct. 

1,476 

55,623 

1,476 

0 

1,352 

0 

214 

0 

Nov. 

1,428 

54,057 

1,428 

0 

1,309 

0 

139 

0 

Dec. 

1,476 

52,609 

1,476 

0 

1,352 

0 

0 

0 

Total  or 

average 

106,085 

50,037 

0 

15,922 

4.235 

2.293 

0 

1904 

Jan. 

1,500 

51,257 

1,500 

0 

1.352 

0 

0 

0 

I'et. 

2,744 

49,905 

2.177 

0 

1,205 

0 

0 

0 

iMar. 

6,813 

49,207 

4,724 

0 

1,352 

0 

0 

0 

April 

5,337 

49,944 

5,337 

0 

1,309 

0 

188 

0 

May 

4,089 

48,447 

4,089 

0 

1,352 

0 

250 

0 

June 

1,517 

46,845 

1,517 

0 

1,309 

0 

296 

0 

July 

861 

45,240 

861 

0 

1,352 

0 

343 

0 

Aug. 

793 

43,545 

793 

0 

1,352 

0 

313 

0 

Sept. 

643 

41,880 

643 

0 

1,309 

0 

238 

0 

Oct. 

738 

40,333 

738 

0 

1,352 

0 

179 

0 

Nov. 

762 

38,802 

762 

0 

1,309 

0 

115 

0 

Dec. 

1,039 

37,378 

1,039 

0 

1,352 

0 

0 

0 

Total  or 

average 

26,836 

24,180 

0 

15,965 

0 

1.922 

0 

1905 

Jan. 

2,251 

36,026 

2,251 

0 

1,352 

0 

0 

0 

Feb. 

25,880 

34,674 

8,206 

0 

1,222 

0 

0 

0 

Mar. 

7,5,140 

51,126 

9,281 

13,658 

1,352 

0 

0 

0 

April 

19,580 

101,975 

9,042 

0 

1.309 

5.949 

303 

0 

May 

17,090 

104,952 

9,344 

0 

1,352 

8,237 

411 

0 

June 

8,271 

102,698 

7,960 

0 

1,309 

9,875 

470 

0 

July 

5,103 

91.355 

5,103 

0 

1,352 

10,266 

512 

0 

Aug. 

2,631 

79,225 

2,631 

0 

1,352 

10,266 

432 

0 

Sept. 

1,869 

67,175 

1.869 

0 

1,309 

9.935 

300 

0 

Oct. 

1,770 

55,631 

1,770 

0 

1.352 

0 

214 

0 

Nov. 

2.660 

54,065 

2,660 

0 

1,309 

0 

139 

0 

Dec. 

2,470 

52,617 

2.470 

0 

1,352 

0 

0 

0 

Total  or 

average 

164,715 

62,587 

13,658 

15,922 

54,528 

2,781 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


409 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  METHODS  OF  FLOOD  CONTROL 
AND  OVER- YEAR  STORAGE, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  15,  page  180.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 
Reservoir  emptied  of  seasonal  storage  each  year. 


Flood  control,  holding  maximum  reservoir  space  required  (131,000  acre-feet)  in  reserve 

throughout  flood  season 

Reser\ 

oir  emptied  each 

summer  to  a  level  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  18  aecond-feet  maintained,  other  drafts  only 

as  required  by  reservoir  operating  diagram 

Flood 

control 

Stage  of 
reservoir 

at 
beginning 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 
passing 
Azusa 
during 
flood  season 
at  rates 
less  than 

Constant 

draft 
from  over- 
year storage 
(18  second- 
feet)  in 
acre-feet 

Seasonally 

stored 

water  in 

acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

Year  and 
month 

1,900  second- 

feet  in 

acre-feet 

1903 

20,884 

2,536 

0 

1,107 

0 

0 

0 

Jan. 

26,341 

5,497 

0 

999 

0 

0 

0 

Feb. 

25,510 

7,898 

0 

1,107 

0 

0 

0 

Mar. 

32.307 

9,042 

11,429 

1,071 

0 

192 

0 

April 

57,700 

9,116 

0 

1,107 

61 

286 

0 

May 

60,473 

5,653 

0 

1,071 

892 

345 

0 

June 

58,165 

2,644 

0 

1.107 

922 

397 

0 

July 

55,739 

1,783 

0 

1,107 

922 

361 

0 

Aug. 

53,349 

1,488 

0 

1,071 

952 

272 

0 

Sept. 

51,054 

],476 

0 

1,107 

839 

202 

0 

Oct. 

48,906 

1,428 

0 

1,071 

0 

131 

0 

Nov. 

47,704 

1,476 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

50.037 

11,429 

13,032 

4,588 

2,186 

0 

1904 

46,597 

1.500 

0 

1,107 

0 

0 

0 

Jan. 

45,490 

2.177 

0 

1,035 

0 

0 

0 

Feb. 

45,022 

4,724 

0 

1,107 

0 

0 

0 

Mar. 

46,004 

5,337 

0 

1,071 

0 

178 

0 

April 

44,755 

4,089 

0 

1,107 

0 

240 

0 

May 

43,408 

1,517 

0 

1,071 

0 

282 

0 

June 

42,055 

861 

0 

1,107 

0 

327 

0 

July 

40,621 

793 

0 

1,107 

0 

297 

0 

Aug. 

39.217 

643 

0 

1,071 

0 

230 

0 

Sept. 

37,916 

738 

0 

1,107 

0 

171 

0 

Oct. 

36,638 

762 

0 

1.071 

0 

111 

0 

Nov. 

35,456 

1,039 

0 

1.107 

0 

0 

0 

Dec. 
Total  or 
average 

24,180 

0 

13,068 

0 

1,836 

0 

1905 

34,349 

2,251 

0 

1.107 

0 

0 

0 

Jan. 

33,242 

8,200 

795 

999 

0 

0 

0 

Feb. 

49,122 

9,281 

64,752 

1,107 

0 

0 

0 

Mar. 

49,122 

9,042 

7,463 

1,071 

0 

188 

0 

April 

50.938 

9,344 

0 

1,107 

0 

270 

0 

May 

57,307 

7,960 

0 

1,071 

238 

333 

0 

June 

55,976 

5,103 

0 

1,107 

369 

389 

0 

July 

54,111 

2.631 

0 

1,107 

369 

357 

0 

Aug. 

52.278 

1,869 

0 

1,071 

357 

270 

0 

Sept. 

50,580 

1.770 

0 

1,107 

401 

202 

0 

Oct 

48,870 

2,660 

0 

1,071 

0 

131 

0 

Nov. 

47,668 

2,470 

0 

1,107 

0 

0 

0 

Doc. 
Total  or 
average 

62,587 

73,010 

13,032 

1,734 

2,140 

0 

26—52411 


410 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  15a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

COORDINATED  WITH  SEASONAL 

Monthly  Summary  of  Computa 

(For  corresponding  yeady  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180.000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Flood  control  by  reservoir  operating  diagram 

Reservoir  emptied  each  summer  to  a  lovt 

1  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  22  second-feet  maintained,  othe 

drafts  only 

as  required  by  reservoir  operating  diagram 

Flood 

Year  and 
month 

Run-off 

at  Azusa 

in  acre-feet 

Stage  of 
reservoir 

at 
beginning 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
aore-feet 

control 
water 

passing 

Azusa 

during 

flood  season 

at  rates 

less  than 

Constant 

draft 
from  over- 
year storage 
(22  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

1.900  second- 

feet  in 

acre-feet 

1906 

Jan. 

4,240 

51,265 

3,633 

0 

1.352 

0 

0 

0 

Feb. 

3,960 

50,520 

3,960 

0 

1.222 

0 

0 

0 

Mar. 

129,000 

49,298 

7,.561 

23,905 

1.352 

0 

0 

0 

April 

34,000 

145,420 

9,042 

15.432 

1,309 

13,028 

357 

0 

May 

21,000 

140,852 

9,344 

0 

1,352 

15,553 

498 

0 

June 

15,500 

135,105 

9,042 

0 

1,309 

17,843 

569 

0 

July 

9,350 

121,842 

8,664 

0 

1.352 

20,527 

609 

0 

Aug. 

4,490 

100,040 

4,990 

0 

1,352 

20,774 

488 

0 

Sept. 

2,840 

77,420 

2.840 

0 

1,309 

20,043 

315 

0 

Oct. 

2,450 

55,759 

2.450 

0 

1,352 

0 

214 

0 

Nov. 

2,400 

54,193 

2,400 

0 

1,309 

0 

139 

0 

Dec. 

11,000 

52,745 

4.030 

0 

1,352 

0 

0 

0 

Total  or 

average 

241,430 

67.456 

39.397 

15,922 

107,768 

3,189 

0 

1907 

Jan. 

58,400 

58,903 

9.217 

51.921 

1,352 

0 

0 

0 

Feb. 

47,100 

54,873 

8.439 

29.904 

1,222 

0 

0 

0 

Mar. 

llii,000 

02,408 

9,344 

45.814 

1,352 

0 

0 

0 

April 

58,100 

121,898 

9,042 

0 

1,309 

9,221 

375 

0 

May 

21,500 

100,351 

9,344 

0 

1,352 

19.487 

539 

0 

June 

15,100 

151,129 

9,042 

0 

1,309 

21,773 

609 

0 

July 

8,300 

133,490 

7,920 

0 

1,352 

24,406 

642 

0 

Aug. 

5,390 

107,476 

5.390 

0 

1,352 

24.651 

402 

0 

Sept. 

3,580 

81,011 

3,580 

0 

1,309 

23,737 

321 

0 

Oct. 

4,090 

55,044 

4,090 

0 

1,352 

0 

214 

0 

Nov. 

3,800 

54,078 

3,800 

0 

1,309 

0 

139 

0 

Dec. 

3,000 

52,630 

3,600 

0 

1,352 

0 

0 

0 

Total  or 
average 

345,320 

82,808 

127,639 

15,922 

123,335 

3..301 

0 

1908 

Jan. 

11,100 

51,278 

4.973 

5,543 

1.352 

0 

0 

0 

Feb. 

15,000 

50,510 

8.741 

4,616 

1,205 

0 

0 

0 

Mar. 

12,700 

50,888 

9,2,i5 

0 

1.352 

0 

0 

0 

April 

i),280 

52,981 

8,056 

0 

1,309 

0 

196 

0 

\lay 

7,190 

52,100 

7,139 

0 

1,352 

0 

262 

0 

June 

4,190 

50,537 

4,190 

0 

1,309 

0 

309 

0 

July 

2,560 

48.(>19 

2,560 

0 

1,352 

0 

359 

0 

Aug. 

2,210 

47,208 

2,210 

0 

1.352 

0 

325 

0 

Sept. 

1,820 

45.531 

1,820 

0 

1,300 

0 

252 

0 

Oct. 

2,070 

43,970 

2.070 

0 

1,352 

0 

186 

0 

Nov. 

1,960 

42.432 

1.960 

0 

1,309 

0 

123 

0 

Dec. 

2.870 

41,000 

2,870 

0 

1.352 

0 

0 

0 

Tot-»l  or 
average 

72.950 

50,444 

10,159 

15,965 

0 

2.012 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


411 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  METHODS  OF  FLOOD  CONTROL 
AND  OVER- YEAR  STORAGE 
tions  Carried  out  on  a  Daily  Basis. 

mary,  sec  Table  15,  page  180.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 
Reservoir  emptied  of  seasonal  storage  each  year. 


Flood  control,  holding  maximum  reservoir  space  required  (131,000  acre-feet)  in  reserve 

throughout  flood  season 

Reservoir  emptied  each 

summer  to  a  level  that  wojU  maintain  constant  draft  through  cri 

tical 

period;  constant  draft  of  18  second-feet  maintained,  other  drafts  only 

as  required  by  reservoir  operating  diagram 

Flood 

control 
water 

Constant 

Year  and 
month 

Stage  of 
reservoir 

at 
licginning 
iif  month 
ill  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

passing 
Azusa 
during 
flood  season 
at  rates 
less  than 

draft 
from  over- 
year storage 
(18  second- 
feet)  in 
acre-feet 

Seasonally 

stored 

water  in 

acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

1,900  second- 

feet  in 

acre-feet 

1906 

46,561 

3,633 

0 

1,107 

0 

0 

0 

Jan. 

46,061 

3,960 

0 

999 

0 

0 

0 

Feb. 

45,062 

7,561 

69,126 

1,107 

0 

0 

0 

Mar. 

96,268 

9,042 

62,426 

1,071 

0 

224 

0 

April 

58,105 

9,344 

0 

1,107 

123 

295 

0 

May 

68,236 

9,042 

0 

1,071 

2,439 

377 

0 

June 

70,807 

8,664 

0 

1,107 

4,242 

442 

0 

July 

65,702 

4,490 

0 

1,107 

4.488 

391 

0 

Aug. 

59,716 

2,840 

0 

1,071 

4,283 

286 

0 

Sept. 

54,076 

2,450 

0 

1,107 

3,801 

204 

0 

Oct. 

48,964 

2,400 

0 

1,071 

0 

131 

0 

Nov. 

47,762 

4,030 

5,103 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

67,456 

136,655 

13,032 

19,376 

2,350 

0 

1907 

49,122 

9,217 

48,076 

1,107 

0 

0 

0 

Jan. 

49,122 

8,439 

37.662 

999 

0 

0 

0 

Feb. 

49,122 

9,344 

98,043 

1,107 

0 

0 

0 

Mar. 

56,628 

9,042 

44,649 

1,071 

0 

100 

0 

April 

60,070 

9,344 

0 

1,107 

430 

303 

0 

May 

70,386 

9,042 

0 

1,071 

2.915 

385 

0 

June 

72,073 

7,920 

0 

1,107 

4,610 

448 

0 

July 

60,348 

5,390 

0 

1,107 

4,733 

395 

0 

Aug. 

60,113 

3.580 

0 

1,071 

4,581 

290 

0 

Sept. 

54,171 

4,090 

0 

1,107 

3.960 

204 

0 

Oct. 

48,900 

3,800 

0 

1,071 

0 

131 

0 

Nov. 

47,698 

3,600 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

82,808 

228,430 

13,032 

21,229 

2.352 

0 

1908 

46,591 

4.973 

2.489 

1,107 

0 

0 

0 

Jan. 

49,122 

8,741 

5.224 

1,035 

0 

0 

0 

Feb. 

49,122 

9,255 

2,338 

1,107 

0 

0 

0 

Mar 

49.122 

8.656 

305 

1.071 

0 

190 

0 

April 

48,180 

7,139 

0 

1,107 

0 

250 

0 

May 

40,874 

4,190 

0 

1,071 

0 

295 

0 

June 

45,508 

2,.560 

0 

1,107 

0 

343 

0 

July 

44,058 

2,210 

0 

1,107 

0 

313 

0 

Aug. 

42.638 

1,820 

0 

1,071 

0 

240 

0 

Sept. 

41.327 

2.070 

0 

1,107 

0 

180 

0 

Oct. 

40.040 

1,960 

0 

1,071 

0 

117 

0 

Nov. 

38,852 

2,870 

0 

1,107 

0 

0 

0 

Dec. 

Total  or 
average 

56,444 

10,356 

13.068                         0 

1.928 

0 

412 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  15a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

COORDINATED  WITH  SEASONAL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Flood  control  by 

reservoir  operating  diagram 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  22  second-feet  maintained,  othe 

r  drafts  only 

as  required  by 

eservoir  operating  diagram 

Flood 

Year  and 
month 

Run-off 
_  at  Azusa 
in  acre-feet 

Stage  of 
reservoir 

at 
beginning 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

control 
water 

pissing 

Azusa 

during 

flood  season 

at  rates 

less  than 

Constant 

draft 
from  over- 
year storage 
(22  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

1,900  second- 

feet  in 

acre-feet 

1909 

Jan. 

25,500 

39,648 

5,596 

8,681 

1,352 

0 

0 

0 

Feb. 

59,400 

49,519 

8,440 

41,897 

1,222 

0 

0 

0 

Mar. 

26,300 

57,360 

9,344 

0 

1,352 

0 

0 

0 

April 

28,000 

72,964 

9.042 

0 

1,309 

1,190 

258 

0 

May 

15,200 

89,165 

9,344 

0 

1,352 

5,041 

369 

0 

June 

8,570 

88,259 

8,319 

0 

1,309 

6,306 

428 

0 

July 

5,040 

80,467 

5,040 

0 

1,352 

6,639 

478 

0 

Aug. 

3,120 

71,998 

3,120 

0 

1.352 

6,578 

412 

0 

Sept. 

2,320 

63,656 

2.320 

0 

1,309 

6,365 

295 

0 

Oct. 

2,310 

55,687 

2,310 

0 

1,352 

0 

214 

0 

Nov. 

2,880 

54,121 

2,880 

0 

1.309 

0 

139 

0 

Dec. 

20,900 

52.673 

6,346 

1,682 

1,352 

0 

0 

0 

Total  or 
average 

199,540 

72,101 

52,260 

15,922 

32,119 

2,593 

0 

1910 

Jan. 

69,500 

64,193 

9,344 

72,870 

1,352 

0 

0 

0 

Feb. 

11,500 

50,127 

8,435 

2,292 

1,222 

0 

0 

0 

Mar. 

9,590 

49,678 

9,029 

0 

1,352 

0 

0 

0 

April 

8,270 

48,887 

8,120 

0 

1,303 

0 

186 

0 

May 

5,050 

47,542 

5,050 

0 

1,352 

0 

250 

0 

June 

3,560 

45,940 

3,560 

0 

1,309 

0 

291 

0 

July 

2,450 

44,340 

2,450 

0 

1,352 

0 

337 

0 

Aug 

1,710 

42,051 

1,710 

0 

1,352 

0 

307 

0 

Sept. 

1,370 

40,992 

1,370 

0 

1,309 

0 

234 

0 

Oct. 

1,560 

39,449 

1,560 

0 

1,352 

0 

174 

0 

Nov. 

1,870 

37,923 

1,870 

0 

1,309 

0 

113 

0 

Dec. 
Total  or 
average 

2,020 

36,501 

2,020 

0 

1,352 

0 

0 

0 

118,450 

54,518 

75,162 

15,922 

0 

1,892 

0 

1911 

Jan. 

37.200 

35,149 

6.441 

6,949 

1,352 

0 

0 

0 

Feb. 

44,300 

57,607 

8,440 

38,010 

1,222 

0 

0 

0 

Mar. 

122,000 

54,235 

9,344 

65.857 

1,352 

0 

0 

0 

April 

28,200 

109,682 

9,042 

0 

1,309 

7.198 

325 

0 

May 

16,600 

120,008 

9,344 

0 

1,.352 

11,311 

446 

0 

June 

7.500 

114,155 

7,322 

0 

1,309 

12,671 

502 

0 

July 

6,230 

99.851 

5,230 

0 

1,352 

13,155 

537 

0 

Aug. 

3,610 

84,807 

3.610 

0 

1,352 

13.094 

446 

0 

Sept. 

2.8,30 

69,915 

2,830 

0 

1,309 

12,612 

306 

0 

Oct. 

3,140 

55,688 

3,140 

0 

1,352 

0 

215 

0 

Nov. 

2,800 

54,121 

2,800 

0 

1,309 

0 

139 

0 

Doc. 
Total  or 
average 

2,870 

52,673 

2.870 

0 

1,352 

0 

0 

0 

276,280 

70,413 

100,816 

15,922 

70,041 

2.916 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


413 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  METHODS  OF  FLOOD  CONTROL 
AND  OVER- YEAR  STORAGE, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  15,  page  180.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 
Reservoir  emptied  of  seasonal  storage  each  year. 


Flood  control,  holding  maximum  reservoir  space  required  (131,000  acre-feet)  in  reserve 

throughout  flood  season 

Reservoir  emptied  each 

summer  to  a  level  that  would  maintain  constant  draft  through  cr 

tical 

period;  constant  draft  of  18 

second-feet  maintained,  other  drafts  only 

as  required  by 

reservoir  operating  diagram 

Flood 

Stage  of 
reservoir 

at 
beginning 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

control 
water 
passing 
Azusa 
during 
flood  season 
at  rates 
less  than 

Constant 

draft 
from  over- 
year storage 
(18  second- 
feet)  in 
acre-feet 

Seasonally 

stored 

water  in 

acre-feet 

1  Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

Year  and 
month 

1,900  second. 

feet  in 

acre-feet 

1909 

37,745 

5,596 

7,420 

1,107 

0 

0 

0 

Jan. 

49,122 

8,440 

49,961 

999 

0 

0 

0 

Feb. 

49,122 

9,344 

15,849 

1,107 

0 

0 

0 

Mar. 

49,122 

9,042 

12,977 

1,071 

0 

192 

0 

April 

53,840 

9,344 

0 

1,107 

0 

276 

0 

May 

58,313 

8,319 

0 

1,071 

476 

337 

0 

June 

56,680 

5,040 

0 

1,107 

553 

393 

0 

July 

54,627 

3,120 

0 

1,107 

553 

357 

0 

Aug. 

52,610 

2,320 

0 

1,071 

535 

272 

0 

Sept. 

50,732 

2,310 

0 

1,107 

527 

205 

0 

Oct. 

48,893 

2,880 

0 

1,071 

0 

133 

0 

Nov. 

47,689 

6,346 

5,208 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

72,101 

91,415 

13,032 

2,644 

2,165 

0 

1910 

55,928 

9,344 

65,855 

1,107 

0 

0 

0 

Jan. 

49,122 

8,435 

2,147 

999 

0 

0 

0 

Feb. 

49,041 

9,029 

0 

1,107 

0 

0 

0 

Mar. 

48,495 

8,120 

0 

1,071 

0 

186 

0 

April 

47,388 

5,050 

0 

1,107 

0 

248 

0 

May 

46,033 

3,560 

0 

1,071 

0 

292 

0 

June 

44,670 

2,450 

0 

1,107 

0 

341 

0 

July 

43,222 

1,710 

0 

1,107 

0 

311 

0 

Aug. 

41,804 

1,370 

0 

1,071 

0 

238 

0 

Sept. 

40,495 

1,560 

0 

1,107 

0 

178 

0 

Oct. 

39,210 

1,870 

0 

1,071 

0 

117 

0 

Nov. 

38,022 

2,020 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 

54,518 

68,002 

13,032 

0 

1,911 

0 

average 
1911 

36,915 

6,441 

10,419 

1,107 

0 

0 

0 

Jan. 

56,148 

8,440 

41,887 

999 

0 

0 

0 

Feb. 

49,122 

9,344 

99,133 

1,107 

0 

0 

0 

Mar. 

61,538 

9,042 

24,943 

1,071 

0 

194 

0 

April 

54,488 

9,344 

0 

1,107 

0 

280 

0 

May 

60,357 

7,322 

0 

1,071 

892 

345 

0 

June 

58,227 

5,230 

0 

1,107 

984 

397 

0 

July 

55,739 

3,610 

0 

1,107 

922 

361 

0 

Aug. 

53,349 

2,830 

0 

1,071 

952 

272 

0 

Sept. 

51,054 

3,140 

0 

1,107 

867 

201 

0 

Oct. 

48,876 

2,800 

0 

1,071 

0 

141 

0 

Nov. 

47,664 

2,870 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

70,413 

176,382 

13,032 

4,617 

2,194 

0 

414 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  15a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

COORDINATED  WITH  SEASONAL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Flood  control  by 

reservoir  operating  diagram 

Reservoir  em 

ptied  each  summer  to  a  leve 

1  that  would  maintain  constant  draft  throu 

gh  critical 

period;  consta 

it  draft  of  22  second-feet  maintained,  othci 

drafts  only 

as  required  by  reservoir  operating  diagram 

Flood 

Year  and 
month 

Run-off 
_  at  Azusa 
in  acre-feet 

Stage  of 
reservoir 

at  _ 
beginning 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

control 
water 
passing 
Azusa 
during 

flood  season 
at  rates 
less  than 

1.900  second- 
feet  in 
acre-feet 

Constant 

draft 
from  over- 
year storage 
(22  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

1912 

Jan. 

2,710 

51,321 

2,710 

0 

1,352 

0 

0 

0 

Feb. 

2,230 

49,969 

2,230 

0 

1265 

0 

0 

0 

Mar. 

22,900 

48,704 

8,199 

0 

1,352 

0 

0 

0 

April 

18,000 

62,053 

8,515 

0 

1,309 

0 

238 

0 

May 

10,900 

69,991 

8,828 

0 

1,352 

1,168 

315 

0 

June 

4,990 

69.228 

4,990 

0 

1.309 

1,606 

373 

0 

July 

3,000 

65,940 

3.060 

0 

1,352 

1,660 

426 

0 

Aug. 

1,960 

62,502 

1.960 

0 

1,352 

1,660 

359 

0 

Sept. 

1,5.50 

59,131 

1.550 

0 

1,309 

1,067 

291 

0 

Oct. 

1,830 

55,864 

1.830 

0 

1,352 

0 

215 

0 

Nov. 

1,730 

54,297 

1.730 

0 

1,309 

0 

139 

0 

Dec. 

1.760 

52,849 

1.760 

0 

1.352 

0 

0 

0 

Total  or 
average 

73,620 

47,362 

0 

15.965 

7,761 

2.356 

0 

1913 

Jan. 

2,910 

51,497 

2,910 

0 

1.352 

0 

0 

0 

Feb. 

13,200 

50,145 

4,753 

0 

1.222 

0 

0 

0 

Mar. 

10.200 

57,370 

8,759 

0 

1.352 

0 

0 

0 

April 

7,140 

57,459 

7,091 

0 

1.309 

0 

206 

0 

May 

4,970 

55,993 

4,970 

0 

1,352 

0 

274 

0 

June 

2,890 

54.367 

2.890 

0 

1,309 

0 

321 

0 

July 

1,690 

52.737 

1.690 

0 

1,352 

0 

375 

0 

Auk. 

1,070 

51.010 

1.070 

0 

1,352 

0 

340 

0 

Sept. 

893 

49,318 

893 

0 

1.309 

0 

260 

0 

Oct. 

910 

47.749 

910 

0 

1,.352 

0 

196 

0 

Nov. 

2,280 

46.201 

2,280 

0 

1,309 

0 

127 

0 

Dec. 

2,170 

44,765 

2,170 

0 

1.352 

0 

0 

0 

Total  or 
avcroKC 

50,323 

40.386 

0 

15.922 

0 

2,099 

0 

1914 

Jan. 

61,400 

43.413 

6,271 

35,050 

1,352 

0 

0 

0 

Feb. 

121,000 

62.140 

8.440 

58,284 

1.222 

0 

0 

0 

Mar. 

48,000 

115.194 

9.344 

52,388 

1.352 

0 

0 

0 

April 

21,400 

100.110 

9.042 

0 

1.309 

5,652 

301 

0 

May 

16.900 

105,206 

9.344 

0 

1.352 

8,299 

410 

0 

June 

9.580 

102,701 

8.585 

0 

1,.309 

9,875 

472 

0 

July 

5.570 

92,040 

5.570 

0 

1,.3.52 

10,512 

516 

0 

AUR. 

3.630 

79,000 

3.630 

0 

1,352 

10.450 

432 

0 

Sept. 

2.7.30 

67.426 

2.730 

0 

1,309 

10.113 

301 

0 

Oct. 

2.770 

55.703 

2.770 

0 

1,352 

0 

214 

0 

Nov. 

2,440 

.54.137 

2.440 

0 

1,309 

0 

139 

0 

Dec. 

4,290 

52.689 

4.290 

0 

1,352 

0 

0 

0 

Total  or 
average 

290,710 

72,456 

145,722 

15,922 

54.901 

2.785 

0 

THE    CONTROL   OF   FLOODS   BY   RESERVOIRS. 


415 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  METHODS  OF  FLOOD  CONTROL 
AND  OVER- YEAR  STORAGE, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  15,  page  180.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 
Reservoir  emptied  of  seasonal  storage  each  year. 


Flood  control,  holding  maximum  reservoir  space  required  (131,000  acre-feet)  in  reserve 

throuqhout  flood  season 

Reser\ 

oir  emptied  each  summer  to  a  level  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  18  second-feet  maintained,  other  drafts  only 

as  required  by  reservoir  operating  diagram 

Flood 

control 

Year  and 

Stage  of 
reser^'oir 

at 
beginning 
of  month 
in  acre-feet 

water 

Constant 

month 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

passing 

Azusa 

during 

flood  season 

at  rates 

less  than 

draft 
from  over- 
year storage 
(18  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

1,900  second- 

feet  in 

acre-feet 

1912 

46,557 

2,710 

0 

1,107 

0 

0 

0 

Jan. 

45,450 

2,230 

0 

1,035 

0 

0 

0 

Feb. 

44,415 

8,199 

9,208 

1,107 

0 

0 

0 

Mar. 

48,801 

8,515 

3,852 

1,071 

0 

192 

0 

April 

53,171 

8,828 

0 

1,107 

0 

268 

0 

May 

53,868 

4,990 

0 

1,071 

0 

321 

0 

June 

52,476 

3,060 

0 

1,107 

0 

375 

0 

July 

50,994 

1,960 

0 

1,107 

0 

341 

0 

Aug 

49,546 

1.550 

0 

1,071 

0 

262 

0 

Sept 

48,213 

1,830 

0 

1,107 

0 

196 

0 

Qjt. 

46,910 

1,730 

0 

1,071 

0 

127 

0 

Nov 

45,712 

1,760 

0 

1,107 

0 

0 

0 

Dec 
Total  or 
average 

47,362 

13,060 

13,068 

0 

2,082 

0 

1913 

44,605 

2,910 

0 

1,107 

0 

0 

0 

Jan. 

43,498 

4,753 

1,824 

999 

0 

0 

0 

Feb. 

49,122 

8,759 

863 

1,107 

0 

0 

0 

Mar. 

48.593 

7,091 

0 

1,071 

0 

186 

0 

April 

47,385 

4,970 

0 

1,107 

0 

248 

0 

May 

46.030 

2,890 

0 

1,071 

0 

292 

0 

June 

44,667 

1,690 

0 

1,107 

0 

341 

0 

July 

43,219 

1,070 

0 

1,107 

0 

311 

0 

Aug. 

41,801 

893 

0 

1,071 

0 

238 

0 

Sept. 

40,492 

910 

0 

1,107 

0 

178 

0 

Oct. 

39,207 

2,280 

0 

1,071 

0 

115 

0 

Nov. 

38,021 

2,170 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

40,386 

2,687 

13,032 

0 

1,909 

0 

1914 

36,914 

6,271 

30,155 

1,107 

0 

0 

0 

Jan. 

60,781 

8,440 

60,518 

999 

0 

0 

0 

Feb. 

111,824 

9,344 

100,251 

1,107 

0 

0 

0 

Mar. 

49,122 

9,042 

6,877 

1,071 

0 

190 

0 

April 

53,.342 

9,344 

0 

1,107 

0 

278 

0 

May 

59,513 

8,585 

0 

1,071 

714 

343 

0 

June 

58,380 

5,570 

0 

1,107 

984 

397 

0 

July 

55,892 

3,630 

0 

1,107 

984 

361 

0 

Aug. 

53,440 

2,730 

0 

1,071 

952 

272 

0 

Sept. 

51,145 

2,770 

0 

1,107 

920 

204 

0 

Oct. 

48,914 

2,440 

0 

1,071 

0 

131 

0 

Nov. 

47,712 

4,290 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

1              72,456 

197.801 

13,032 

4,554 

2,176 

0 

416 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  15a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

COORDINATED  WITH  SEASONAL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Flood  control  by 

reservoir  operating  diagram 

Reser^'oir  emptied  each  summer  to  a  leve 

Ithat  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  22  second-feet  maintained,  other  drafts  only 

af 

required  by  reservoir  operating  diagram 

I 

Flood 

Year  and 
month 

Run-off 

at  Azusa 

in  acre-feet 

Stage  of 
reseri-oir 

at 
beginning 
of  month 
in  aere-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

control 
water 

passing 

Azusa 

during 

flood  season 

at  rates 

less  than 

Constant 

draft 
from  over- 
year storage 
(22  second- 
feet)  in 
aere-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

l,900second- 

feet  in 

acre-feet 

1915 

Jan. 

7,380 

51,-337 

4.428 

3,629 

1,352 

0 

0 

0 

Feb 

30,200 

49.308 

8.412 

12,355 

1,222 

0 

0 

0 

Mar. 

21,500 

57,519 

9,344 

0 

1,352 

0 

0 

0 

April 

17.300 

68,323 

9.042 

0 

1,309 

416 

238 

0 

May 

20,400 

74,618 

9,344 

0 

1,352 

2,090 

341 

0 

June 

11,400 

81.891 

8,967 

0 

1,309 

4.759 

414 

0 

July 

7.010 

77,842 

7.010 

0 

1,352 

5,717 

468 

0 

Aug. 

3,980 

70,305 

3.980 

0 

1,352 

5,717 

407 

0 

Sept. 

3,270 

62,829 

3.270 

0 

1,309 

5,533 

293 

0 

Oct. 

2,770 

55.694 

2.770 

0 

1,352 

0 

214 

0 

Nov. 

3,010 

54,128 

3.010 

0 

1,309 

0 

139 

0 

Dec. 

3,580 

52,680 

3,580 

0 

1,352 

0 

0 

0 

Total  or 
average 

131,800 

73.157 

15,984 

15,922 

24,232 

2,514 

0 

1916 

Jan. 

148,000 

51,328 

8,759 

51,935 

1,352 

0 

0 

0 

Feb. 

39,400 

137,282 

8,741 

99,779 

1,265 

0 

0 

0 

Mar. 

34,800 

66,897 

9.344 

603 

1.352 

0 

0 

0 

April 

19,000 

90,398 

9,042 

0 

1,309 

4.045 

284 

0 

May 

10,400 

95,618 

9.130 

0 

1,352 

6.393 

379 

0 

June 

5,830 

88,764 

5,830 

0 

1,309 

6.484 

430 

0 

July 

4,770 

80,541 

4,770 

0 

1,352 

6.6.39 

480 

0 

Aug. 

3,570 

72,070 

3,570 

0 

1,352 

6,639 

412 

0 

Sept. 

2,810 

63,667 

2.810 

0 

1,309. 

6,425 

295 

0 

Oct. 

7,010 

55.638 

6.473 

0 

1.352 

0 

214 

0 

Nov. 

4,130 

54,609 

4.130 

0 

1,309 

0 

131 

0 

Dec 

13,600 

53.169 

5.253 

0 

1.352 

0 

0 

0 

Total  or 
average 

294.220 

77.852 

152.317 

15,965 

36,625 

2,625 

0 

1917 

Jan. 

9,280 

60.164 

8.172 

10,464 

1.352 

0 

0 

0 

Feb. 

13.200 

49.456 

7,551 

0 

1.222 

0 

0 

0 

Mar. 

13.600 

53.883 

9,344 

0 

1.352 

0 

0 

0 

April 
May 

10,500 

56.787 

9,042 

0 

1,309 

0 

208 

0 

8,610 

56.728 

8,531 

0 

1,352 

0 

276 

0 

June 

5,270 

5.5,179 

5.270 

0 

1,309 

0 

327 

0 

July 

3.140 

53,543 

3,140 

0 

1,352 

0 

379 

0 

Aug. 

2,200 

51.812 

2,200 

0 

1.352 

0 

345 

0 

Sept. 

1,510 

50.115 

1,510 

0 

1,.309 

0 

262 

0 

Oct. 

1.560 

48.544 

1.560 

0 

1,352 

0 

198 

0 

Nov. 

1.840 

46.994 

1,840 

0 

1,309 

0 

127 

0 

Dec. 

2.000 

45.558 

2,000 

0 

1,352 

0 

0 

0 

Total  or 
average 

72.710 

60.160 

10,464 

15,922 

0 

2,122 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


417 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  METHODS  OF  FLOOD  CONTROL 
AND  OVER- YEAR  STORAGE, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  15,  page  180.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 
Reservoir  emptied  of  seasonal  storage  each  year. 


Flood  control,  holding  maximum  reservoir  space  required  (131,000  acre-feet)  in  reserve 

throughout  flood  season 

Reservoir  emptied  each 

summer  to  a  level  that  would  maintain  constant  draft  through  cr 

tical 

period:  constant  draft  of  18 

second-feet  maintained,  other  drafts  only 

as  required  by- 

reservoir  operating  diagram 

Flood 

control 

Year  and 

Stage  of 

reservoir 

at 

Passed 
by  dam 

water 
passing 
Azusa 
during 

Constant 

draft 
from  over- 

Seasonally 
stored 

Evaporation 
from_ 

Waste 
over 

month 

beginning 
of  month 
in  acre-feet 

for  prior 
rights  in 
acre-feet 

flood  season 
at  rates 
less  than 
1,900  second- 
feet  in 
acre-feet 

year  storage 
(18  second- 
fee  tl  in 
acre-feet 

water  in 
acre-feet 

reservoir 
surface  in 
acre-feet 

spillway 
in  acre-feet 

1915 

46,605 

4,428 

0 

1,107 

0 

0 

0 

Jan. 

48,450 

8,412 

20,117 

999 

0 

0 

0 

Feb. 

49,122 

9,344 

11,049 

1,107 

0 

0 

0 

Mar. 

49,122 

9,042 

4,689 

1,071 

0 

188 

0 

April 

51,432 

9,344 

0 

1,107 

0 

276 

0 

May 

61,105 

8,967 

0 

1,071 

1,011 

349 

0 

June 

61,107 

7,010 

0 

1,107 

1,721 

408 

0 

July 

57,871 

3,980 

0 

1,107 

1,721 

369 

0 

Aug. 

54,674 

3,270 

0 

1,071 

1,666 

276 

0 

Sept. 

51,661 

2,770 

0 

1,107 

1,499 

204 

0 

Oct. 

48,851 

3,010 

0 

1,071 

0 

131 

0 

Nov. 

47,649 

3,580 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

73,157 

35,855 

13,032 

7,618 

2,201 

0 

1916 

46,542 

8,759 

52,105 

1,107 

0 

0 

0 

Jan. 

132,571 

'8,741 

100,650 

1,035 

0 

0 

0 

Feb. 

61,545 

9,344 

36,772 

1,107 

0 

0 

0 

Mar. 

49,122 

9,042 

7,311 

1,071 

0 

190 

0 

April 

51,408 

9,130 

0 

1,107 

0 

262 

0 

May 

51,309 

5,830 

0 

1,071 

0 

311 

0 

June 

49,927 

4,770 

0 

1,107 

0 

363 

0 

July 

48,457 

3,570 

0 

1,107 

0 

331 

0 

Aug. 

47,019 

2,810 

0 

1,071 

0 

254 

0 

Sept. 

45,694 

6,473 

0 

1,107 

0 

190 

0 

Oct. 

44,934 

4,130 

0 

1,071 

0 

127 

0 

Nov. 

43,736 

5,253 

1,997 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

77,852 

198,835 

13,068 

0 

2,028 

0 

1917 

48,979 

8,172 

98 

1,107 

0 

0 

0 

Jan. 

48,882 

7,551 

4,410 

999 

0 

0 

0 

Feb. 

49,122 

9,344 

3,149 

1,107 

0 

0 

0 

Mar. 

49,122 

9,042 

370 

1,071 

0 

190 

0 

April 

48,949 

8,531 

0 

1,107 

0 

252 

0 

May 

47,669 

5,270 

0 

1,071 

0 

299 

0 

June 

46,299 

3,140 

0 

1,107 

0 

347 

0 

July 

44,845 

2,200 

0 

1,107 

0 

317 

0 

Aug. 

43,421 

1,510 

0 

1,071 

0 

242 

0 

Sept. 

42,108 

1,560 

0 

1,107 

0 

182 

0 

Oct. 

40,819 

1,840 

0 

1,071 

0 

117 

0 

Nov. 

39,631 

2,000 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 
avcrasc 

60,160 

8,027 

13,032 

0 

1,946 

0 

418 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  15a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

COORDINATED  WITH  SEASONAL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Flood  control  bv 

reservoir  operating  diagram 

Reser\'oir  emptied  each  summer  to  a  level  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  22 

second-feet  maintained,  other  drafts  only 

as  required  by 

reservoir  operating  diagram 

Flood 

Year  and 
month 

Run-off 

at  Azusa 

in  acre-feet 

Stage  of 
reservoir 

at 
beginning 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

control 

water 

passing 

Azusa 

during 
flood  season 

at  rates 

less  than 

l,900second- 

feet  in 
acre-feet 

Constant 

draft 
from  over- 
year storage 
(22  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

1918 

Jan. 

2,020 

44.206 

2,020 

0 

1,352 

0 

0 

0 

Feb. 

9,330 

42,854 

3,847 

0 

1,222 

0 

0 

0 

Mar. 

73,200 

47,115 

9,249 

3,595 

1,352 

0 

0 

0 

April 

17,000 

106,119 

9,042 

0 

1,309 

6,603 

307 

0 

May 

10,000 

105,858 

8.993 

0 

1,352 

8,422 

412 

0 

June 

6,010 

96,679 

6,010 

0 

1,309 

8,388 

454 

0 

July 

3,970 

86,528 

3.970 

0 

1,352 

8.668 

496 

0 

Aug. 

2,840 

76,012 

2,840 

0 

1.352 

8,606 

422 

0 

Sept. 

2,330 

65,632 

2,330 

0 

1,309 

8,329 

297 

0 

Oct. 

2,930 

55,697 

2,930 

0 

1,352 

0 

214 

0 

Nov. 

3,140 

54,131 

3,140 

0 

1,309 

0 

139 

0 

Dec. 

4,370 

52,683 

4,370 

0 

1,352 

0 

0 

0 

Total  or 
average 

137,140 

58,741 

3,595 

15.922 

49.016 

2,741 

0 

1919 

Jan. 

3,300 

51,331 

3,300 

0 

1,352 

0 

0 

0 

Feb. 

4,110 

49,979 

4,110 

0 

1,222 

0 

0 

0 

Mar. 

6,110 

48,757 

6.110 

0 

1,352 

0 

0 

0 

April 

6.010 

47,405 

6.010 

0 

1,309 

0 

182 

0 

May 

3,810 

45,914 

3,810 

0 

1,352 

0 

244 

0 

June 

1,890 

44,318 

1,890 

0 

1.309 

0 

284 

0 

July 

1,320 

42,725 

1,320 

0 

1.352 

0 

329 

0 

Aug. 

935 

41,044 

935 

0 

1,352 

0 

299 

0 

Sept. 

1,010 

39,393 

1,010 

0 

1,309 

0 

230 

0 

Oct. 

2,040 

37,854 

2,040 

0 

1.352 

0 

171 

0 

Nov. 

2,130 

36.331 

2,130 

0 

1,309 

0 

109 

0 

Dec. 

5,340 

34,913 

5,209 

0 

1,352 

0 

0 

0 

Total  or 
average 

38,005 

37.874 

0 

15,922 

0 

1.848 

0 

1920 

Jtm. 

3,260 

33.692 

3,260 

0 

1,352 

0 

0 

0 

Feb. 

12,700 

32.340 

5.854 

0 

1.265 

0 

0 

0 

Mar. 

36,200 

37,921 

9,344 

0 

1.352 

0 

0 

0 

April 
May 

25.100 

63,425 

9.042 

0 

1.309 

0 

236 

0 

12,600 

77,938 

9.344 

0 

1,352 

2.766 

339 

0 

Juno 

7.380 

76.737 

7.349 

0 

1,309 

3.510 

395 

0 

July 

4,670 

71,554 

4,670 

0 

1,352 

3.565 

446 

0 

Aug. 

3,200 

66.191 

3,200 

0 

1.352 

3.627 

395 

0 

Sept. 

2.030 

60.817 

2,030 

0 

1,300 

3.510 

290 

0 

Oct. 

2,000 

55.708 

2.000 

0 

1,352 

0 

214 

0 

Nov. 

2.380 

51.142 

2.380 

0 

1.309 

0 

139 

0 

Dec. 

2.210 

52,694 

2.210 

0 

1,352 

0 

0 

0 

Total  or 

average 

113.730 

60,683 

0 

15.965 

16.978 

2.454 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


419 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  METHODS  OF  FLOOD  CONTROL 
AND  OVER- YEAR  STORAGE, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  15,  page  180.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 
Reservoir  emptied  of  seasonal  storage  each  year. 


Flood  control,  holding  maximum  reservoir  space  required  (131,000  acre-feet)  in  reserve 

throughout  flood  season 

Reserv 

oir  emptied  each 

summer  to  a  level  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  18  second-feet  maintained,  other  drafts  only 

as  required  by  reservoir  operating  diagram 

Flood 

control 

Year  and 

Stage  of 
reservoir 

at  _ 

beginning 

of  montii 

■  n  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 

passing 
Azusa 
during 
flood  season 
at  rates 
less  than 

Constant 

draft 
from  over- 
year storage 
(18  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

month 

1,900  second- 

feet  in 

acre-feet 

1918 

38,524 

2,020 

0 

1,107 

0 

0 

0 

Jan. 

37,417 

3,847 

0 

999 

0 

0 

0 

Feb. 

41,901 

9,249 

55,023 

1,107 

0 

0 

0 

Mar. 

49,122 

9,042 

5,345 

1.071 

0 

190 

0 

April 

50,474 

8,993 

0 

1.107 

0 

258 

0 

May 

50,116 

6,010 

0 

1,071 

0 

305 

0 

.Tune 

48,740 

3,970 

0 

1.107 

0 

359 

0 

July 

47,274 

2,840 

0 

1,107 

0 

327 

0 

Aug. 

45,840 

2,330 

0 

1.071 

0 

252 

0 

Sept. 

■♦4,517 

2,930 

0 

1.107 

0 

188 

0 

Oct. 

43,222 

3,140 

0 

1.071 

0 

121 

0 

Nov. 

42,030 

4,370 

0 

1.107 

0 

0 

0 

Dec. 

Total  or 
average 

58,741 

60,968 

13,032 

0 

2,000 

0 

1919 

40,923 

3,300 

0 

1,107 

0 

0 

0 

Jan. 

39,816 

4,110 

0 

999 

0 

0 

0 

Feb. 

38,817 

6,110 

0 

1,107 

0 

0 

0 

Mar. 

37,710 

6,010 

0 

1,071 

0 

161 

0 

April 

36,478 

3,810 

0 

1.107 

0 

214 

0 

May 

35,157 

1,890 

0 

1.071 

0 

250 

0 

June 

33,836 

1,320 

0 

1.107 

0 

290 

0 

July 

32,439 

935 

0 

1.107 

0 

262 

0 

Aug. 

31,070 

1,010 

0 

1.071 

0 

200 

0 

Sept 

29,799 

2.040 

0 

1.107 

0 

149 

0 

Oct. 

28,543 

2,130 

0 

1.071 

0 

97 

0 

Nov. 

27,375 

5.209 

0 

1.107 

0 

0 

0 

Deo. 

Total  or 
average 

37.874 

0 

13.032 

0 

1,623 

0 

1920 

26.399 

3,260 

0 

1.107 

0 

0 

0 

Jan. 

25,292 

5,854 

0 

1,035 

0 

0 

0 

Feb. 

31,103 

9,344 

7.730 

1,107 

0 

0 

0 

Mar. 

49,122 

9,042 

12.388 

1,071 

0 

190 

0 

April 

51,531 

9,344 

0 

1,107 

0 

266 

0 

May 

53,414 

7,349 

0 

1,071 

0 

319 

0 

June 

52,055 

4,670 

0 

1,107 

0 

371 

0 

July 

50.577 

3,200 

0 

1.107 

0 

339 

0 

Aug. 

49,131 

2,030 

0 

1,071 

0 

260 

0 

Sept 

47,800 

2,000 

0 

1.107 

0 

196 

0 

Oct. 

46,497 

2,380 

0 

1.071 

0 

127 

0 

Nov. 

45,299 

2,210 

0 

1,107 

0 

0 

0 

Dec. 

Total  or 
average 

60,683 

20,118 

13.068 

0 

2,068 

0 

420 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  15a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

COORDINATED  WITH  SEASONAL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Flood  confrol  by 

reservoir  operating  diagram 

Reservoir  en 

ptied  each  summer  to  a  leve 

1  that  would  maintain  constant  draft  throu 

gh  critical 

period;  constant  draft  of  22  s 

econd-feet  maintained,  other 

drafts  only 

as 

required  by  reser\-oir  operating  diagram 

Flood 

Year  and 
month 

Run-off 

at  Azusa 

in  acre-feet 

Stage  of 
reservoir 

at 
beginning 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

control 
water 

passing 

Azusa 

during 

flood  season 

at  rates 

less  than 

Constant 

draft 
from  over- 
year storage 
(22  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Wasio 

over 

spillway 

in  acre-feet 

1,900  second- 

feet  in 

acre-feet 

1921 

Jan. 

5,160 

51,342 

4,405 

0 

1,.3.52 

0 

0 

0 

Feb. 

4,490 

50,745 

4.490 

0 

1  222 

0 

0 

0 

Mar. 

15,400 

49,523 

7,288 

0 

l!352 

0 

0 

0 

April 

6,070 

56,283 

6,070 

0 

1,309 

0 

204 

0 

May 

15,700 

54,770 

6,835 

0 

1,3.52 

0 

281 

0 

June 

8,980 

62,002 

7,920 

0 

1,309 

0 

354 

0 

July 

3,830 

61,399 

3,830 

0 

1,3.52 

184 

413 

0 

Aug. 

2,450 

59,450 

2,450 

0 

1,352 

184 

378 

0 

Sept. 

1,840 

57,536 

1,840 

0 

1,309 

238 

286 

0 

Oct. 

2,040 

55,703 

2,040 

0 

1,352 

0 

214 

0 

Nov. 

1,800 

54,137 

1,800 

0 

1,309 

0 

139 

0 

Dec. 

119,000 

52,689 

5,045 

39,506 

1,352 

0 

0 

0 

Total  or 
average 

186,760 

54,013 

39,506 

15,922 

606 

2.269 

0 

1922 

Jan. 

62,100 

125,786 

9,344 

107,332 

1,352 

0 

0 

0 

Feb. 

88,900 

69,858 

8,440 

83,316 

1.222 

0 

0 

0 

Mar. 

47,800 

65,780 

9,344 

2,882 

1,.352 

0 

0 

0 

April 

31.400 

100,002 

9,042 

0 

1,309 

5.65? 

311 

0 

May 

24,700 

115,088 

9,344 

0 

l,3.i2 

10,327 

446 

0 

June 

14,400 

118,319 

9,042 

0 

1,30<.) 

13,742 

522 

0 

July 

0,100 

108.104 

8,.576 

0 

1,352 

15,922 

565 

0 

Aug. 

5,080 

90,789 

5,080 

0 

1,3.52 

16,106 

464 

0 

Sept. 

3,290 

72,867 

3,290 

0 

1,309 

15,527 

307 

0 

Oct. 

3,110 

55,724 

3,110 

0 

1,3.52 

0 

214 

0 

Nov. 

.5,310 

54,158 

4,519 

0 

1,.309 

0 

141 

0 

Dec. 

21,500 

53,499 

8,456 

1,990 

1,352 

0 

0 

0 

Total  or 
average 

316.690 

87,587 

195,520 

15,922 

77.276 

2.970 

0 

1923 

Jan. 

7,1.30 

63,201 

6.968 

12.058 

1.352 

0 

0 

0 

Feb. 

7,830 

49,955 

7.791 

0 

1.222 

0 

0 

0 

Mar. 

7,320 

48,772 

7.320 

0 

1.352 

0 

0 

0 

April 
May 

8,3.30 

47,420 

8.079 

0 

1,309 

0 

182 

0 

5,480 

46,180 

5,480 

0 

1,352 

0 

244 

0 

June 

3,700 

44,584 

3.700 

0 

1,309 

0 

288 

0 

July 

2.420 

42,987 

2,420 

0 

1,352 

0 

331 

0 

Aug. 

1,990 

41, .304 

1,990 

0 

1,352 

0 

299 

0 

Sept. 

1,750 

39,653 

1,750 

0 

1,309 

0 

232 

0 

Oct. 

1.710 

38.112 

1.710 

0 

1,352 

0 

171 

0 

Nov. 

1,960 

36,589 

1,960 

0 

1.309 

0 

111 

0 

Dec. 

2.130 

35.169 

2,130 

0 

1.352 

0 

0 

0 

Total  or 
average 

51,7.50 

51.298 

12,056 

1.5,922 

0 

1,858 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


421 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  METHODS  OF  FLOOD  CONTROL 
AND  OVER- YEAR  STORAGE, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  15,  page  180.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 
Reservoir  emptied  of  seasonal  storage  each  year. 


Flood  control,  holding  maximum  reservoir  space  required  (131,000  acre-feet)  in  reserve 

throughout  flood  season 

Reservoir  emptied  each 

summer  to  a  lev 

jlthat  would  maintain  constant  draft  through  critical 

period;  cons 

tant  draft  of  18 

second-feet  maintained,  other  drafts  only 

as  required  by 

■eservoir  operating  diagram 

Flood 

control 

Year  and 

Stage  of 
reservoir 

at  _ 
begimiing 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 
passing 
Azusa 
during 
flood  season 
at  rates 
less  than 

Constant 

draft 
from  over- 
year storage 
(18  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

month 

1,900  second- 

feet  in 

acre-feet 

1921 

44,192 

4,405 

0 

1,107 

0 

0 

0 

Jan. 

43,840 

4,490 

0 

999 

0 

0 

0 

Feb. 

42,841 

7.288 

899 

1.107 

0 

0 

0 

Mar. 

48,947 

6.070 

0 

1.071 

0 

186 

0 

April 

47,690 

6.835 

0 

1,107 

0 

250 

0 

May 

55,198 

7.920 

0 

1.071 

0 

329 

0 

June 

51,858 

3,830 

0 

1,107 

61 

385 

0 

July 

53,305 

2.450 

0 

1,107 

61 

353 

0 

Aug. 

51,784 

1,840 

0 

1,071 

119 

270 

0 

Sept. 

50,324 

2.040 

0 

1,107 

111 

204 

0 

Oct. 

48,902 

1.800 

0 

1,071 

0 

131 

0 

Nov. 

47,700 

5.045 

45,446 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

54.013 

46,345 

13,032 

352 

2,108 

0 

1922 

115.102 

9.344 

107,317 

1,107 

0 

0 

0 

Jan. 

59.434 

8,440 

86.263 

999 

0 

0 

0 

Feb. 

52.632 

9..344 

40.859 

1,107 

0 

0 

0 

Mar. 

49,122 

9,042 

13,915 

1.071 

0 

192 

0 

April 

56,302 

9,344 

0 

1.107 

0 

297 

0 

May 

70,254 

9.042 

0 

1,071 

2.856 

385 

0 

June 

71,300 

8,576 

0 

1,107 

4,365 

444 

0 

July 

65.908 

5,080 

0 

1,107 

4.549 

393 

0 

Aug. 

59.859 

3,290 

0 

1,071 

4,402 

282 

0 

Sept. 

54.104 

3,110 

0 

1.107 

3.801 

202 

0 

Oct. 

48,994 

4,519 

260 

1.071 

0 

133 

0 

Nov. 

48,321 

8,456 

11.295 

1.107 

0 

0 

0 

-     Dec. 

Total  or 
average 

87,587 

259,909 

13,032 

19,973 

2.328 

0 

1923 

48.963 

6.968 

0 

1,107 

0 

0 

0 

Jan. 

48.018 

7.791 

0 

999 

0 

0 

0 

Feb. 

47,058 

7.320 

0 

1,107 

0 

0 

0 

Mar. 

45,951 

8.079 

0 

1,071 

0 

178 

0 

April 

44,953 

5.480 

0 

1,107 

0 

240 

0 

May 

43,606 

3.700 

0 

1,071 

0 

284 

0 

June 

42,251 

2.420 

0 

1,107 

0 

329 

0 

July 

40,815 

1.990 

0 

1,107 

0 

299 

0 

Aug. 

39,409 

1.7,50 

0 

1,071 

0 

236 

0 

Sept. 

38,102 

1,710 

0 

1.107 

0 

173 

0 

Oct. 

36,822 

1,960 

0 

1,071 

0 

111 

0 

Nov. 

35,640 

2.130 

0 

1.107 

0 

0 

0 

Dec. 
Total  or 

51,298 

0 

13.032 

0 

1,850 

0 

average 

422 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  15a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

COORDINATED  WITH  SEASONAL 

Monthly  Summary  of  Compute 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Flood  control  by 

reservoir  operating  diagram 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  22  second-feet  maintained,  other  drafts  only 

as  required  by 

eservoir  operating  diagram 

Flood 

Year  and 
month 

Run-off 

at  Azusa 

in  acre-feet 

Stage  of 
reservoir 

at 
beginning 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
aore-fect 

control 
water 

passing 
Azusa 

during 
flood  season 

at  rates 

less  than 
l.gOOsecond- 

feet  in 

acre-feet 

Constant 

draft 
from  over- 
year storage 
(22  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

1924 

Jan. 

2,170 

33,817 

2,170 

n 

1,352 

0 

0 

0 

Feb. 

1,790 

32,465 

1,790 

(1 

1,265 

0 

0 

0 

Mar. 

4,130 

31,200 

3,714 

0 

1,352 

0 

0 

0 

April 

0,190 

30,264 

6,190 

0 

1,309 

0 

141 

0 

May 

3,650 

28,814 

3,650 

0 

1,352 

0 

186 

0 

June 

1,660 

27,276 

1,660 

0 

1,309 

0 

214 

0 

July 

1,000 

25,753 

1,000 

0 

1,352 

0 

248 

0 

Aug. 

756 

24,153 

756 

0 

1,352 

0 

222 

0 

Sept. 

744 

22,579 

744 

0 

1,309 

0 

167 

0 

Oct. 

873 

21,103 

873 

0 

1,352 

0 

123 

0 

Nov. 

1,190 

19,628 

1,190 

0 

1,.309 

0 

79 

0 

Dec. 
Total  or 

1,780 

18,240 

1,780 

0 

1,352 

0 

0 

0 

average 

25,933 

25,517 

0 

15,965 

0 

1,380 

0 

1925 

Jan. 

1,710 

16,888 

1,710 

0 

1,352 

0 

0 

0 

Feb. 

1,620 

15,536 

1,620 

0 

1,222 

0 

0 

0 

Mar. 

2,510 

14,314 

2,423 

0 

1,352 

0 

0 

0 

April 

7,200 

13,049 

5,765 

n 

1,309 

0 

89 

0 

May 

3,050 

13,086 

3,050 

0 

1,352 

0 

105 

0 

J.ine 

1,840 

11,629 

1,840 

0 

1,309 

0 

131 

0 

July 

824 

10,189 

824 

,  0 

1,352 

0 

141 

0 

Aug. 

621 

8,696 

621 

0 

1,3.52 

0 

117 

0 

.Sept. 

492 

7,227 

492 

0 

1,309 

0 

81 

0 

(let. 

873 

5,837 

873 

0 

1.352 

0 

52 

0 

Nov. 

1,010 

4,433 

1,010 

0 

1,309 

0 

28 

0 

Dec. 
Total  or 
average 

1,050 

3,096 

1,650 

0 

1,352 

0 

0 

0 

23,400 

21.878 

0 

15,922 

0 

744 

0 

1926 

Jan. 

1,540 

1,744 

1,540 

0 

1,352 

0 

0 

0 

I'cb. 

7,lt40 

392 

5,485 

0 

1,222 

0 

0 

0 

Mar. 

3,650 

1,625 

3,650 

0 

1.352 

0 

0 

0 

April 

69,000 

273 

8,233 

0 

1,309 

0 

159 

0 

May 

13,000 

59,572 

9,142 

I) 

1,352 

0 

293 

0 

June 

5,500 

61,785 

5,500 

0 

1,309 

0 

349 

0 

July 

3,120 

60,127 

3,120 

0 

1,352 

0 

408 

0 

Aug. 

2,070 

58,367 

2,070 

0 

1.352 

0 

373 

0 

Sept. 

1,580 

56,642 

1,580 

0 

1,309 

0 

284 

0 

Oct. 

55.049 

Nov. 

Dfc. 
Total  or 
average 

107.400 

40.320 

0 

11.909 

0 

1,866 

0 

THE    CONTROL   OF    FLOODS   BY    RESERVOIRS. 


423 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  METHODS  OF  FLOOD  CONTROL 
AND  OVER- YEAR  STORAGE, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  15,  page  180.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 
Reservoir  emptied  of  seasonal  storage  each  year. 


Flood  control,  holding  maximum  reservoir  space  required  (131,000  acre-feef)  in  reserve 
throughout  flood  season 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  18  second-feet  maintained,  other  drafts  only 

as  required  by  reservoir  operating  diagram 


Flood 

control 

Year  and 

Stage  of 
reservoir 

at  _ 
beginning 
of  month 
in  acre-feet 

water 

Constant 

month 

Passed 
ty  dam 
for  prior 
rights  in 
acre-feet 

passing 
Azusa 
during 
flood  season 
at  rates 
less  than 

draft 
from  over- 
year storage 
(18  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre- feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  aore-feet 

1,900  second- 

feet  in 

acre-feet 

1924 

34,533 

2,170 

0 

1,107 

0 

0 

0 

Jan. 

33,426 

1,790 

0 

1,035 

0 

0 

0 

Feb. 

32,391 

3,714 

0 

1,107 

0 

0 

0 

Mar. 

31,700 

6,190 

0 

1,071 

0 

147 

0 

April 

30.482 

3,650 

0 

1,107 

0 

192 

0 

May 

29,183 

1,660 

0 

1,071 

0 

224 

0 

June 

27,888 

1,000 

0 

1,107 

0 

260 

0 

July 

26,521 

756 

0 

1,107 

0 

236 

0 

Aug. 

25,178 

744 

0 

1,071 

0 

178 

0 

Sept. 

23,929 

873 

0 

1,107 

0 

131 

0 

Oct. 

22,691 

1,190 

0 

1,071 

0 

85 

0 

Nov. 

21,535 

1,780 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

25,517 

0 

13,068 

0 

1,453 

0 

1925 

20,428 

1,710 

0 

1,107 

0 

0 

0 

Jan. 

19,321 

1,620 

0 

999 

0 

0 

0 

Feb. 

18,322 

2,423 

0 

1,107 

0 

0 

0 

Mar. 

17,302 

5,765 

0 

1,071 

0 

105 

0 

April 

17,561 

3,050 

0 

1,107 

0 

141 

0 

May 

16,313 

1,840 

0 

1,071 

0 

163 

0 

June 

15,079 

824 

0 

1,107 

0 

184 

0 

July 

13,788 

621 

0 

1,107 

0 

163 

0 

Aug. 

12,518 

492 

0 

1,071 

0 

117 

0 

Sept. 

11,330 

873 

0 

1,107 

0 

85 

0 

Oct. 

10,138 

1,010 

0 

1,071 

0 

52 

0 

Nov. 

9,015 

1,650 

0 

1,107 

0 

0 

0 

Dec. 
Total  or 
average 

21,878 

0 

13.032 

0 

1,010 

0 

1926 

7,908 

1,540 

0 

1,107 

0 

0 

0 

Jan. 

6,801 

5,485 

0 

999 

0 

0 

0 

Feb. 

8,257 

3,650 

0 

1,107 

0 

0 

0 

Mar. 

7,150 

8,233 

11,836 

1,071 

0 

165 

0 

April 

54,845 

9,142 

0 

1,107 

0 

276 

0 

May 

57,320 

5,500 

0 

1,071 

238 

319 

0 

June 

55,692 

3,120 

0 

1,107 

246 

387 

0 

July 

53,952 

2,070 

0 

1,107 

307 

355 

0 

Aug. 

52,183 

1,580 

0 

1,071 

297 

270 

0 

Sept. 

50,545 

Oct. 

Nov. 

Dec. 
Total  or 
average 

40,320 

11,836 

9,747 

1,088 

1.772 

0 

424 


WATER  RESOURCES  OP    CALIFORNIA. 


TABLE  15a  (Concluded).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

COORDINATED  WITH  SEASONAL 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 

Natural  flow  up  to  152  second-feet  passed  for  prior  rights. 


Run-off 
at  Azusa 
in  acre-feet 

Flood  control  by  reservoir  operating  diagram 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant  draft  through  critical 

period;  constant  draft  of  22  second-feet  maintained,  other  drafts  only 

as  required  by  reservoir  operating  diagram 

Year  and 
month 

Stage  of 
reservoir 

at 
beginning 
of  month 
in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

Flood 

control 
water 

passing 

Azusa 

during 

flood  season 

at  rates 

less  than 
1,900  second- 
feet  in 

acre-feet 

Constant 

draft 
from  over- 
year storage 
(22  second- 
feet)  in 
acre-feet 

Seasonally 
stored 
water  in 
acre-feet 

Evaporation 

from 

reservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

Total  for 

period, 

Jan.1, 

1897,  to 

Oct.1, 

1926 

Average 

for 

period, 

Jan.1, 

1897,  to 

Oct.1, 

1926 

3,731,977 
125.445 

1,513,303 
50,867 

"1,010,662 
"33.972 

473,905 
15,930 

676,322 
22,734 

65,386 
2,198 

0 

"  These  figures  contain  7601  aore-feet  total  or  an  average  of  256  acre-feet  per  season  of  water  contributed  from  outside 
t  lie  exact  period  of  analysis.  In  the  computations  from  which  this  table  is  prepared,  the  wafer  in  storage  on  October  1,  1926, 
the  end  of  the  psriod,  is  less  by  this  amount  than  on  January  I.  1897,  the  beginning  of  the  period.  Since  in  the  computations 
tliis  water  wis  released  as  fljod  cjntrol  water  during  the  first  flood  season  of  the  period,  the  exact  yield  of  flood  control  water 
for  the  period  is  less  than  here  shown  by  this  amount. 


THE    CONTROL   OP   FLOODS   BY    RESERVOIRS. 


425 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  METHODS  OF  FLOOD  CONTROL 
AND  OVER- YEAR  STORAGE, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  15,  page  180.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 
Reservoir  emptied  of  seasonal  storage  each  year. 


Flood  control,  holding  maximum  reservoir  space  required  (131,000  acre-feet)  in  reserve 

throughout  flood  season 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant  draft  through  cr 

period;  constant  draft  of  18  second-feet  maintained,  other  drafts  only 

as  required  by  reservoir  operating  diagram 

tical 

Stage  of 
reservoir 

at 

begirming 

of  month 

in  acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

Flood 
control 
water 
passing 
Azusa 
during 
flood  season 
at  rates 
less  than 
1,900  second- 
feet  in 
acre-feet 

Constant 

draft 
from  over- 
year storage 
(18  second- 
feet)  in 
acre-feet 

Seasonally 

stored 

water  in 

acre-feet 

Evaporation 

from 

I'eservoir 

surface  in 

acre-feet 

Waste 

over 

spillway 

in  acre-feet 

Year  and 
month 

1,513,303 
50,867 

1,685,053 
56,641 

387,891 
13,039 

87,773 
''2,950 

56,534 
1,900 

0 
0 

Total  for 
period, 
Jan. 1, 
1897,  to 
Oct.  1, 
1926 

Average 

for 

period, 

Jan.1. 

1897,  to 

Oct.1, 

1926 

^  In  the  computations  for  this  table,  the  period  of  analysis  closed  with  1423  acre-feet  more  water  in  storage  than  at  the 
beginning,  the  equivalent  of  48  acre-feet  per  season.  Since  in  the  computations  this  water  was  stored  in  the  last  year  of  the 
period  of  analysis,  the  exact  yield  in  seasonally  stored  water  for  the  period  is  larger  than  here  shown  by  this  amount 


2T— 52411 


426 


WATER  RESOURCES  OF    CALIFORNIA. 

TABLE  16a.     SAN  GABRIEL  RESER 

COMPARISON  OF  WATER  YIELD  FOR 

USE  OF  RES 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 


Natural  flow  up  to  152  second- 


Flood  control  alone 

Flood  control  .irtlally 

Water  drawn  from 

reservoir  or 

ly  as  require 

dby 

Constant  draft  o 

r  22  second- 

reservoir  operating  diagram 

only  as 

required  by 

Flood 

Flood 

Run-off 

control 

control 

at 

vpater 

water 

month 

Azusa 

in 

acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

passmg 
Azusa 
during 
flood 
season 

at  rates 

less 

than  1.900 

second- 
feet  in 

acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

passmg 
Azusa 
during 
flood 
season 

at  rates 

less 

than  1,900 

second- 
feet  in 

acre-feet 

1897 

Jan. 

3,617 

62,650 

3,017 

13,131 

0 

0 

62,650 

3,617 

11,779 

Feb. 

10,148 

49,519 

7,262 

5,432 

0 

0 

49,519 

7,262 

4,628 

Mar. 

28,623 

55,971 

9,344 

0 

0 

0 

55,553 

9,344 

0 

April 

17.519 

75,250 

9,042 

0 

238 

0 

73,480 

9,042 

0 

May 

8,8.51 

83,489 

8,126 

0 

369 

0 

80,413 

8,126 

0 

June 

4,033 

83,845 

4,033 

0 

426 

0 

79,433 

4.033 

0 

July 

2,343 

83,419 

2,343 

0 

504 

0 

77,712 

2,343 

0 

Aug. 

1,613 

82,915 

1,613 

0 

466 

0 

75,875 

1,613 

0 

Sept. 

1,226 

82,449 

1,226 

0 

359 

0 

74,083 

1,226 

0 

Oct. 

5,564 

82,090 

2,622 

0 

280 

0 

72,437 

2,622 

0 

Nov. 

1,860 

84,752 

1,860 

0 

188 

0 

73,769 

1.860 

0 

Dec. 

1,875 

84.564 

1,875 

11,646 

0 

0 

72,289 

1,875 

0 

Total  or 
average 

96,270 

52,963 

30,209 

2,830 

0 

52,963 

16.407 

1898 

Jan. 

2,453 

72.918 

2,453 

13,484 

0 

0 

70,937 

2,453 

10,849 

Feb. 

2,241 

.59,434 

2,241 

0 

0 

0 

58,736 

2,241 

0 

Mar. 

2,131 

59,434 

2,131 

0 

0 

0 

57,514 

2,131 

0 

April 

1,9.50 

59,434 

1.9.50 

0 

210 

0 

56,162 

1,950 

0 

May 

2,213 

59,224 

2,213 

0 

286 

0 

54,651 

2.213 

0 

June 

1,1.59 

58,938 

1,159 

0 

343 

0 

53.029 

1,159 

0 

July 

672 

58,595 

672 

0 

403 

0 

51.395 

672 

0 

Aug. 

456 

58,192 

456 

0 

375 

0 

49,674 

456 

0 

Sept. 

467 

57,817 

467 

0 

289 

0 

47,985 

467 

0 

Oct. 

533 

57.528 

5.33 

0 

222 

0 

46,420 

533 

0 

Nov. 

580 

57.306 

580 

0 

145 

0 

44,876 

580 

0 

Dec. 
Total  or 
average 

832 

57.161 

832 

0 

0 

0 

43,442 

832 

0 

15.687 

15,687 

13,484 

2,273 

0 

15,687 

10,849 

1899 

Jan. 

1,414 

57,161 

1,414 

0 

0 

0 

42,090 

1,414 

0 

Feb. 

1,244 

57,161 

1,244 

0 

0 

0 

40.738 

1,244 

0 

Mar. 

1,023 

57,161 

1,623 

0 

0 

0 

39.516 

1,623 

0 

April 

1,262 

57,161 

1,262 

0 

206 

0 

38.164 

1,262 

0 

May 

842 

56,955 

842 

0 

280 

0 

36.694 

842 

0 

June 

565 

56.675 

565 

0 

333 

0 

35,128 

565 

0 

July 

221 

56..342 

221 

0 

393 

0 

33,571 

221 

0 

Aug. 

295 

55,949 

295 

0 

366 

0 

31.931 

295 

0 

Sept. 

220 

55,583 

220 

0 

28 1 

0 

30,319 

220 

0 

Oct. 

683 

55,299 

683 

0 

214 

0 

28,812 

683 

0 

Nov. 

847 

55,085 

847 

0 

143 

0 

27,313 

847 

0 

Dec. 
Total  or 
average 

1,247 

54,942 

1.247 

0 

0 

0 

25.913 

1,247 

0 

10.463 

10,463 

0 

2,219 

' 

10,463 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


427 


VOIR  ON  SAN  GABRIEL  RIVER. 

THREE  STEPS  IN  COORDINATING  THE 

ERVOIR  SPACE. 

tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  16,  page  182.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights. 

Flood  control  completely  coordinated  with  conservation 

coordinated  with  conservation 

Reservoir  emptied 

each  summer  to  a  level  that  would  maintain  constant 

feet  maintained,_  othe_ 

r  drafts 

draft  through 

critical  period:  constant  draft  of  22  second-feet 

reservoir  operating  diagram 

maintained,  othe 

r  drafts  only  as  requir 

ed  by 

reservoir  operating  diagram 

Flood 

control 

Constant 

draft 

from 

over-year 

storage 

(22 
second- 
feet)  in 
acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 

passing 

Azusa 

during 

flood 

season 

at  rates 

less 

than  1,900 

spcond- 

feet  in 

acre-feet 

Constant 

draft 

from 

over-year 

storage 

(22 
second- 
feet)  in 
acre-feet 

Variable 

summer 

draft 

from 

seasonally 

stored 

water  in 

acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre  feet 

Waste 

over 

spillway 

in 
acre-feet 

Year  and 
month 

1897 

1,352 

0 

0 

62,650 

3,617 

11,779 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

49,519 

7,262 

4,628 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

55,553 

9,344 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

235 

0 

73,480 

9,042 

0 

1,309 

1,249 

234 

0 

April 

1,352 

353 

0 

79,165 

8,126 

0 

1,352 

3,012 

343 

0 

May 

1,309 

412 

0 

75,183 

4,033 

0 

1,309 

3,093 

396 

0 

June 

1,352 

485 

0 

70,385 

2,343 

0 

1,352 

3,197 

447 

0 

July 

1,352 

440 

0 

65,389 

1,613 

0 

1,352 

3,197 

393 

0 

Aug. 

1,309 

337 

0 

60,447 

1,226 

0 

1,309 

3,153 

290 

0 

Sept. 

1,352 

258 

0 

55,695 

2,622 

0 

1,352 

0 

220 

0 

Oct. 

1,309 

171 

0 

57,005 

1,860 

0 

1,309 

0 

143 

0 

Nov. 

1,352 

0 

0 

55,613 

1,875 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 
average 

15,922 

2,691 

0 

52,963 

16,407 

15,922 

16,901 

2,466 

0 

1898 

1,352 

0 

0 

54,261 

2,453 

0 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

52,909 

2,241 

0 

1  222 

0 

0 

0 

Feb. 

1,352 

0 

0 

51,687 

2,131 

0 

i;352 

0 

0 

0 

Mar. 

1,309 

202 

0 

50,335 

1,950 

0 

1,309 

n 

190 

0 

April 

1.352 

270 

0 

48,836 

2,213 

0 

1,352 

0 

252 

0 

May 

1,309 

325 

0 

47,232 

1,159 

0 

1,309 

0 

296 

0 

June 

1,352 

369 

0 

45,627 

672 

0 

1,352 

0 

.343 

0 

July 

1,352 

337 

0 

43,932 

456 

0 

1,352 

0 

313 

0 

Aug. 

1,309 

25G 

0 

42,267 

467 

0 

1,309 

0 

238 

0 

Sept. 

1,352 

192 

0 

40,720 

533 

0 

1,352 

0 

179 

0 

Oct. 

1,309 

125 

0 

39,189 

580 

0 

1,309 

0 

115 

0 

Nov. 

1,352 

0 

0 

37,765 

832 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 
average 

15,922 

2,076 

0 

15,687 

0 

15,922 

0 

1,926 

0 

1899 

1,352 

0 

0 

36,413 

1,414 

0 

1,352 

n 

0 

0 

Jan. 

1,222 

0 

0 

35,061 

1,244 

0 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

33,839 

1,623 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

161 

0 

32,487 

1,262 

0 

1.309 

0 

149 

0 

A|>ril 

1,352 

214 

0 

31,029 

842 

0 

1,352 

0 

194 

0 

May 

1,309 

248 

0 

29,483 

565 

0 

1,309 

0 

224 

0 

June 

1,352 

288 

0 

27,950 

221 

0 

1,3,52 

0 

260 

0 

July 

1,352 

260 

0 

26,338 

295 

0 

1,352 

0 

234 

0 

Aug. 

1,309 

198 

0 

21,752 

220 

0 

1309 

0 

175 

0 

Sept. 

1,352 

147 

0 

23,268 

683 

0 

r352 

0 

129 

0 

Oct. 

1,309 

91 

0 

21,787 

847 

0 

1,309 

0 

83 

0 

Nov. 

1,352 

0 

0 

20,395 

1,247 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 
average 

15,922 

1,607 

0 

0 

10,463 

0 

15,922 

0 

1,448 

0 

428 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  16a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

USE  OF  RES 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 


Natural  flow  up  to  152  second- 


Flood  control  alone 

Flood  control  partially 

Water  drawn  froir 

reservoir  only  as  required  by 

Constant  draft  of  22  second- 

reservoir  operating  diagram 

only  as  required  by 

Flood 

Flood 

Runoff 

control 

control 

Year  and 
month 

at 

Azusa 

in 

acre  feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 
passing 
Azusa 
during 
flood 
season 
at  rates 
less 
than  1 ,900 
second- 
feet  in 
acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 
passing 
Azusa 
during 
flood 
season 
at  rates 
less 
than  1,900 
second- 
feet  in 
acre-feet 

1900 

Jan. 

1,968 

54,942 

1.968 

0 

0 

0 

24,561 

1.968 

0 

Feb. 

1,111 

54,942 

1,111 

0 

0 

0 

23,209 

1,111 

0 

Mar. 

1,230 

54,942 

1,230 

0 

0 

0 

21.987 

1,230 

0 

April 

1,012 

54,942 

1,012 

0 

200 

0 

20.635 

1,012 

0 

May 

2,275 

54,742 

2.275 

0 

272 

0 

19.211 

2.275 

0 

June 

893 

54,470 

893 

0 

327 

0 

17.712 

893 

0 

July 

309 

.54,143 

369 

0 

385 

0 

16,223 

369 

0 

Aug. 

246 

63,758 

246 

0 

357 

0 

14.679 

246 

0 

Sept. 

238 

53,401 

238 

0 

276 

0 

13,158 

238 

0 

Oct. 

307 

53.125 

307 

0 

210 

0 

11.728 

307 

0 

Nov. 

11,068 

52.915 

1.058 

0 

139 

0 

10,281 

1,058 

0 

Dec. 

1,269 

62.786 

1,269 

0 

0 

0 

18,923 

1,269 

0 

Total  or 
average 

21,986 

11,976 

0 

2,160 

0 

11,976 

0 

1901 

Jan. 

10,391 

62.786 

6,661 

16,586 

0 

0 

17,571 

6,661 

0 

Feb. 

38,709 

49.930 

8,350 

19.884 

0 

0 

19,949 

8,350 

0 

Mar. 

13,.'589 

60,405 

9,138 

0 

0 

0 

49,086 

9.138 

0 

April 

6,.515 

64,856 

6,545 

0 

224 

0 

52,185 

6,.545 

0 

May 

7,410 

64.632 

6,990 

0 

301 

0 

50.684 

6.990 

0 

June 

3,749 

64,781 

3,749 

0 

363 

0 

49.522 

3,749 

0 

July 

1.845 

64,418 

1,845 

0 

426 

0 

47.908 

1,845 

0 

Aug. 

1,240 

63,992 

1,240 

0 

397 

0 

46,203 

1.240 

0 

Sept. 

1,012 

63,595 

1,012 

0 

305 

0 

44,530 

1,012 

0 

Oct. 

1,476 

63,290 

1,476 

0 

2.34 

0 

42,975 

1,476 

0 

Nov. 

1,904 

63,056 

1.904 

0 

155 

0 

41,439 

1,904 

0 

Dec. 
Total  or 
average 

1,660 

62,901 

1,660 

0 

0 

0 

40,015 

1,660 

0 

89,560 

50.570 

36,470 

2,405 

0 

50,570 

1902 

Jan. 

1,722 

62,901 

1,722 

0 

0 

0 

38,663 

1,722 

0 

Feb. 

2,055 

62,901 

2,055 

0 

0 

0 

37.311 

2.055 

0 

Mar. 

6,088 

62,901 

5.590 

0 

0 

0 

36.089 

5.590 

0 

April 

3,928 

63,399 

3.928 

0 

218 

0 

35,235 

3.928 

0 

May 

2.398 

63.181 

2.398 

0 

295 

0 

33.773 

2,398 

0 

June 

1,190 

62.886 

1.190 

0 

355 

0 

32.217 

1.190 

0 

July 

676 

62,.')31 

676 

0 

420 

0 

30,672 

676 

0 

Aug. 

430 

62,111 

430 

0 

389 

0 

2!),048 

430 

0 

Sept. 

298 

61,722 

298 

0 

301 

0 

27.4.50 

298 

0 

Oct. 

430 

61.421 

430 

0 

228 

0 

25.955 

430 

0 

Nov. 

1,131 

61.193 

1.131 

0 

151 

0 

24.464 

1.131 

0 

Dec. 
Total  or 
average 

1,968 

61.042 

1,968 

0 

0 

0 

23.068 

1,968 

0 

22,314 

21,816 

0 

2,357 

0 

21,816 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


429 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

THREE  STEPS  IN  COORDINATING  THE 

ERVOIR  SPACE. 

tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  16,  page  182.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights. 


Flood  control  completely  coordinated  with  conservation 

coordinated  with  conservation 

Reservoir  emptied  each  summer  to  a  level  that  would 

maintain  constant 

feet  maintained,  other  drafts 

6n 

ft  through  critical  period;  constant  draft  of  22  second-feet 

reservoir  operating  diagram 

maintained,  othe 

r  drafts  only  as  required  by 

reservoir 

operating  diagram 

Flood 

control 

Cons  tant 

draft 

from 

over-year 

storage 

(22 
second- 
feet)  in 
acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
reservoir 

at  _ 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 

for  prior 
rights  in 
acre-feet 

water 
passing 
Azusa 
during 
flood 
season 
at  rates 
less 
than  1,900 
second- 
feet  in 
acre-feet 

Constant 

draft 

from 

over-year 

storage 

(22 
second- 
feet)  in 
acre-feet 

Variable 

summer 

draft 

from 

seasonally 

stored 

water  in 

acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Year  and 
month 

1900 

1.352 

0 

0 

19,043 

1,968 

0 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

17,691 

1,111 

0 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

16,469 

1,230 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

115 

0 

15,117 

1,012 

0 

1,309 

0 

95 

0 

April 

1,352 

147 

0 

13,713 

2,275 

0 

1,352 

0 

121 

0 

May 

1,309 

180 

0 

12,240 

893 

0 

1,309 

0 

135 

0 

June 

1,352 

192 

0 

10,796 

369 

0 

1,352 

0 

149 

0 

July 

1,352 

169 

0 

9,295 

246 

0 

1,352 

0 

123 

0 

Aug. 

1,309 

121 

0 

7,820 

238 

0 

1,309 

0 

85 

0 

Sept. 

1,352 

95 

0 

6,426 

307 

0 

1,352 

0 

56 

0 

Oct. 

1,309 

59 

0 

5,018 

1,058 

0 

1,.309 

0 

32 

0 

Nov. 

1,352 

0 

0 

13,687 

1,269 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 
average 

15,922 

1,078 

0 

11,976 

0 

15,922 

0 

796 

0 

1901 

1,352 

0 

0 

12,.335 

6.661 

0 

1,.352 

0 

0 

0 

Jan. 

1,222 

0 

0 

14,713 

8,350 

0 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

43,850 

9,138 

0 

1,352 

0 

0 

0 

Ma-. 

1,309 

192 

0 

46,P49 

6,545 

0 

1,309 

0 

181 

0 

April 

1,352 

260 

0 

45,459 

6,990 

0 

1,.352 

0 

240 

0 

May 

1,309 

305 

0 

44,317 

3,749 

0 

1,309 

0 

286 

0 

June 

1,352 

353 

0 

42,722 

1,845 

0 

1,352 

0 

329 

0 

July 

1,352 

321 

0 

41,041 

1,240 

0 

1,35? 

0 

300 

0 

Aug. 

1,309 

246 

0 

39,389 

1,012 

0 

1,309 

0 

230 

0 

Sept. 

1,352 

184 

0 

37,850 

1,476 

0 

1,352 

0 

171 

0 

Oct. 

1,309 

115 

0 

36,327 

1,904 

0 

1.309 

0 

109 

0 

Nov. 

1,352 

0 

0 

34,909 

1,660 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 
average 

15,922 

1,976 

0 

50.570 

0 

15,922 

0 

1.846 

0 

1902 

1,352 

0 

0 

33,557 

1,722 

0 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

32.205 

2,055 

0 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

30.983 

5,590 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

153 

0 

30, '29 

3,928 

0 

1,309 

0 

141 

0 

April 

1,352 

204 

0 

28,679 

2,398 

0 

1.352 

0 

184 

0 

May 

1,309 

236 

0 

27,143 

1,190 

0 

1.309 

0 

214 

0 

June 

1,352 

272 

0 

25,620 

676 

0 

1,352 

0 

246 

0 

July 

1352 

246 

0 

24,022 

4.30 

0 

1,352 

0 

222 

0 

Aug. 

1,309 

186 

0 

22,448 

298 

0 

1,309 

0 

167 

0 

Sept. 

1,352 

139 

0 

20,972 

430 

0 

1,352 

0 

123 

0 

Oct. 

1,.309 

87 

0 

19,497 

1,131 

0 

1,309 

0 

77 

0 

Nov. 

1,352 

0 

0 

18,111 

1,968 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 
average 

15,922 

1,523 

0 

21,816 

0 

15.922 

0 

1,374 

0 

430 


WATER  RESOURCES   OF   CALIFORNIA. 


TABLE  16a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

USE  OF  RES 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 


Natural  flow  up  to  152  second- 


Flood  control  alone 

Flood  control  partially 

Water  drawn  from  reser\'oir  only  as  required  by 

Constant  draft  c 

f  22  second- 

reservoir  operating  diagram 

only  as 

required  by 

Flood 

Flood 

Run-off 

control 

control 

Year  and 
month 

at 

Azusa 

in 

acre-feet 

Stage  of 
reservoir 

at_ 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 
passing 
Azusa 
during 
flood 
season 
at  rates 
less 
than  1,900 
second- 
feet  in 
acre-feet 

E\-apora- 

tion  from 

reservoir 

surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
resen'oir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 
passing 
Azusa 
during 
flood 
season 
at  rates 
less 
than  1,900 
second- 
feet  in 
acre-feet 

1903 

Jan. 

9,100 

61,042 

2,536 

12,128 

0 

0 

21,716 

2,536 

0 

Feb. 

5,665 

55,478 

5,497 

5,959 

0 

0 

26,928 

5,497 

0 

Mar. 

15,802 

49,687 

7,898 

0 

0 

0 

25,874 

7,898 

0 

April 

47,127 

57,591 

9,042 

0 

260 

0 

32,426 

9,042 

0 

May 

13,343 

95,416 

9,116 

0 

369 

0 

68,994 

9,116 

0 

June 

5,653 

99,274 

5,653 

0 

476 

0 

Tl,.546 

5,653 

0 

July 

2,644 

98,798 

2.644 

0 

561 

0 

69.852 

2,644 

0 

Aug. 

1,783 

98,237 

1,783 

0 

522 

0 

68,054 

1,783 

0 

Sept. 

1,488 

97,715 

1,488 

0 

403 

0 

66,292 

1,488 

0 

Oct. 

1,476 

97,312 

1,476 

0 

305 

0 

64,670 

1,476 

0 

Nov. 

1,428 

97,007 

1,428 

0 

204 

0 

63,082 

1,428 

0 

Dec. 
Total  or 
average 

1,476 

96,803 

1,476 

0 

0 

0 

61,618 

1.476 

0 

106,985 

50,037 

18,087 

3,100 

0 

50,037 

0 

1904 

Jan. 

1,500 

96,803 

1,500 

0 

0 

0 

60,260 

1,500 

0 

Feb. 

2,744 

96,803 

2,177 

0 

0 

0 

58,914 

2,177 

0 

Mar. 

6,813 

97,370 

4,724 

0 

0 

0 

58,216 

4,724 

0 

April 

5,337 

99,459 

5,337 

0 

295 

0 

58,953 

5,337 

0 

May 

4,089 

99,164 

4,089 

0 

397 

0 

57,436 

4,089 

0" 

June 

1,517 

98,767 

1,517 

0 

476 

0 

55,804 

1,517 

0 

July 

861 

98,291 

861 

0 

559 

0 

51,166 

861 

0 

Aug. 

793 

97,732 

793 

0 

520 

0 

52,431 

793 

0 

Sept. 

643 

97.212 

613 

0 

401 

0 

50,730 

643 

0 

Oct. 

738 

96,811 

738 

0 

305 

0 

49,155 

738 

0 

Nov. 

762 

96,.506 

762 

0 

204 

0 

47,597 

762 

0 

Dec. 
Total  or 
average 

1,039 

96,302 

1,039 

0 

0 

0 

46,155 

1,039 

0 

26,836 

24.180 

0 

3,157 

0 

24,180 

0 

1905 

Jan. 

2,251 

96,302 

2,251 

17.237 

0 

0 

44,803 

2,251 

0 

Feb. 

25,880 

79,065 

8,206 

41,863 

0 

0 

43,461 

8,206 

6,204 

Mar. 

75,140 

54,876 

9,281 

18,198 

0 

0 

53,099 

9,281 

16,231 

April 

19,580 

102,537 

9,042 

0 

313 

0 

101.975 

9,042 

0 

May 

17,090 

112,702 

9,344 

0 

446 

0 

110,893 

9,344 

0 

June 

8,271 

120.062 

7.960 

0 

543 

0 

116,849 

7,960 

0 

July 

5,103 

119,830 

5,103 

0 

639 

0 

115,322 

5,103 

0 

Aug. 

2,631 

119.191 

2.631 

0 

593 

0 

113,349 

2,631 

0 

Sept. 

1,869 

118,598 

1,869 

0 

456 

0 

111,426 

1,869 

0 

Oct. 

1,770 

118,142 

1,770 

0 

347 

0 

109,681 

1,770 

0 

Nov. 

2,660 

1 17,795 

2,660 

14.595 

232 

0 

108,000 

2,660 

3,610 

Dec. 
Total  or 
average 

2,470 

102,908 

2,470 

7.444 

0 

0 

102,861 

2,470 

6,944 

164,715 

62,587 

99,337 

3,569 

0 

62,587 

32,989 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


431 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

THREE  STEPS  IN  COORDINATING  THE 

ERVOIR  SPACE. 

tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  16,  page  182.) 

Maximum  controlled  flow  at  Azvisa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet, 
feet  passed  for  prior  rights. 


Flood  control  completely  coordinated  with  conservation 

coordinated  with  conservation 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant     | 

feet  maintained,  other  drafts 

dra 

't  through  critical  period;  constant  draft  of  22  second-feet 

resen-oir  operating  diagram 

maintained  other  drafts  only  as  required  by 
reservoir  operating  diagram 

Flood 

control 

Constant 
draft 

Evapora- 

Stage of 

water 
passing 
Azusa 
during 

Constant 
draft 

Variable 
summer 

Evapora- 
tion from 

Year  and 
month 

from 

tion  from 

Waste 

reservoir 

Passed 

from 

draft 

Waste 

over-year 

reservoir 

over 

at 

by  dam 

flood 

over-year 

from 

reserv'oir 

over 

storage 

(22 
second- 

surface 

in 
acre-feet 

spillway 

in 
acre-feet 

beginning 

of 
month  in 

for  prior 
rights  in 
acre-feet 

season 

at  rates 

less 

storage 

(22 
second- 

seasonally 
stored 
water  in 

surface 

in 
acre-feet 

spillway 

in 
acre-feet 

feet)  in 
acre-feet 

acre-feet 

than  1,900 
second- 
feet  in 
acre-feet 

feet)  in 
acre-feet 

acre-feet 

1903 

1,352 

0 

0 

16,759 

2,.536 

0 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

21,971 

5,497 

0 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

20,917 

7,898 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

208 

0 

27,469 

9,042 

0 

1,309 

0 

180 

0 

April 

1,352 

323 

0 

64,065 

9,116 

0 

1,352 

0 

307 

0 

May 

1,309 

385 

0 

66,633 

5,6.53 

0 

1,309 

1,012 

365 

0 

June 

1,352 

446 

0 

63,947 

2,644 

0 

l,c52 

1,107 

421 

0 

July 

1,352 

410 

0 

61,067 

1,783 

0 

1,352 

1,045 

379 

0 

Aug. 

1,309 

313 

0 

58,291 

1,488 

0 

1,309 

1,071 

288 

0 

Sept. 

1,352 

236 

0 

55,623 

1,476 

0 

1,352 

0 

214 

0 

Oct. 

1,309 

155 

0 

54,057 

1,428 

0 

1,309 

0 

139 

0 

Nov 

1,352 

0 

0 

52,609 

1,476 

0 

1,.352 

0 

0 

0 

Dec. 
Total  or 

15,922 

2,476 

0 

50,037 

0 

15,922 

4,235 

2,293 

0 

average 
1904 

1,352 

0 

0 

51,257 

1,£00 

0 

1,352 

0 

0 

0 

Jan. 

1,265 

0 

0 

49,905 

2,177 

0 

1,265 

0 

0 

0 

Feb. 

1,352 

0 

0 

49,207 

4,724 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

208 

0 

49,944 

5,337 

0 

1,309 

0 

188 

0 

April 

1,352 

280 

0 

48,447 

4,089 

0 

1,352 

0 

250 

0 

May 

1,309 

329 

0 

46  845 

1,517 

0 

1,309 

0 

2)6 

0 

June 

1,352 

383 

0 

45,240 

861 

0 

1,.352 

0 

343 

0 

July 

1,352 

349 

0 

43,545 

793 

0 

1,352 

0 

313 

0 

Aug. 

1.309 

266 

0 

41,880 

643 

0 

1,309 

0 

238 

0 

Sept. 

1,352 

206 

0 

40,3.33 

738 

0 

1,.352 

0 

179 

0 

Oct. 

1,309 

133 

0 

38,802 

762 

0 

1,309 

0 

115 

0 

Nov. 

1,352 

0 

0 

37,378 

1,039 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 

15,965 

2,154 

0 

24,180 

0 

15,965 

0 

),922 

0 

average 
1905 

1.352 

0 

0 

36,026 

2,251 

0 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

34,674 

8,206 

0 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

51.126 

9,281 

13.658 

1,352 

0 

0 

0 

Mar. 

1,309 

311 

0 

101,975 

9,042 

0 

1,309 

5,949 

303 

0 

April 

1,352 

438 

0 

104,952 

9,344 

0 

1,352          8,237 

411 

0 

May 

1,309 

529 

0 

102,608 

7,960 

0 

1,309          9,875 

470 

0 

June 

1.352 

621 

0 

91,355 

5.103 

0 

1,352        10,266 

512 

0 

July 

1,352 

571 

0 

79,225 

2,631 

0 

1,352 

10,266 

432 

0 

Aug. 

1,309 

436 

0 

67,175 

1,869 

0 

1,309 

9,935 

300 

0 

Sept. 

1,3,52 

329 

0 

55,631 

1,770 

0 

1,352 

0 

214 

0 

Oct. 

1,309 

220 

0 

54.065 

2.660 

0 

1,309 

0 

139 

0 

Nov. 

1,352 

0 

0 

52.617 

2,470 

0 

1,352 

0]               0 

0 

Dec. 
Total  or 

15,922 

3,455 

0 

62,587 

13.658 

15,922 

54,528          2,781 

0 

average 

432 


WATER  RESOURCES  OF    CALIFORNIA. 

TABLE  16a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

USE  OF  RES 
Monthly  Summary  of  Computa 

(For  correspxjnding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 


Natural  flow  up  to  152  second- 


Flood  control  alone 

Flood  control  partially 

Wate 

r  drawn  from  reservoir  oi 

ly  as  required  by 

Constant  draft  o 

f  22  second- 

reservoir  operating  diagram 

only  as  required  by 

Flood 

Flood 

Run-off 

control 

control 

Year  and 
month 

at 

water 

water 

Azusa 

in 

acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

passing 

Azusa 

during 

flood 

season 

at  rates 

less 

than  1,900 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 

acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre  feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

passing 

Azusa 

daring 

flood 

season 

at  rates 

less 

than  1,900 

second- 

second- 

feet  in 

feet  in 

acre-feet 

acre-feet 

1906 

Jan. 

4,240 

95,524 

3,633 

35,700 

0 

0 

94,565 

3,633 

33,608 

Feb. 

3,060 

60,425 

3,960 

0 

0 

0 

60,212 

3,960 

0 

Mar. 

129,000 

60,425 

7,561 

33,037 

0 

0 

58,990 

7,561 

30,250 

April 

34,600 

148,827 

9,042 

20,997 

383 

0 

148,827 

9,042 

20,735 

May 

21,000 

153,005 

9,344 

0 

543 

0 

151,960 

9,.344 

0 

June 

15,500 

164,118 

9,042 

0 

682 

0 

161,723 

9.042 

0 

July 

9,350 

169,894 

8,664 

0 

811 

0 

166,198 

8,664 

0 

Aug. 

4,490 

169.769 

4,490 

0 

756 

0 

164,729 

4,490 

0 

Sept. 

2,840 

169.013 

2,840 

0 

583 

0 

162,639 

2,840 

0 

Oct. 

2,4.i0 

168,430 

2,450 

0 

444 

0 

160,763 

2,450 

0 

Nov. 

2,400 

167,986 

2,400 

14,928 

295 

0 

158,981 

2,400 

5,941 

Dec. 
Total  or 
average 

11,600 

152,763 

4,030 

97,132 

0 

0 

151.445 

4,030 

94,462 

241,430 

67,456 

201.800 

4.497 

0 

67,456 

184,996 

1907 

Jan. 

58,400 

03,201 

9,217 

57,512 

0 

0 

63.201 

9,217 

56,159 

I'ch. 

47,100 

54,872 

8,439 

31,125 

0 

0 

54,873 

8,439 

29.904 

Mar. 

116,000 

62,408 

9,344 

47,166 

0 

0 

62,408 

9,344 

45.814 

April 

58,400 

121,898 

9,042 

528 

393 

0 

121,898 

9,042 

453 

May 

21,500 

170,335 

9,344 

0 

591 

•      1,900 

169,103 

9,344 

0 

June 

15,100 

180,000 

9,042 

0 

720 

5,338 

179,322 

9,042 

0 

July 

8,360 

180,000 

7,920 

0 

849 

188 

180,000 

7.920 

0 

Aug. 

5,390 

179,403 

5,390 

0 

787 

0 

178,241 

5.390 

0 

Sept. 

3,580 

178,616 

3,580 

0 

607 

0 

176,108 

3.580 

0 

Oct. 

4,090 

178,009 

4,090 

8,257 

460 

0 

174,200 

4,090 

3.106 

Nov. 

3,800 

169,292 

3,800 

54,872 

256 

0 

169,292 

3,800 

53,565 

Dec. 
Total  or 
average 

3,600 

114,164 

3,600 

12,600 

0 

0 

114,164 

3,600 

12,164 

345,320 

82,808 

212,060 

4,663 

7,426 

82,808 

201.165 

1908 

Jan. 

11,100 

101,564 

4,973 

2  4. .579 

0 

0 

100,648 

4,973 

24.273 

Feb. 

15,000 

83,112 

8,741 

37,743 

0 

0 

81,150 

8,741 

35,256 

Mar. 

12,700 

51,628 

9,255 

0 

0 

0 

50,888 

9,2.55 

0 

April 
May 

9,280 

,55,073 

8,056 

0 

202 

0 

52.i;81 

8,656 

0 

7,190 

55,495 

7.139 

0 

337 

0 

52,100 

7,139 

0 

June 

4,190 

55.209 

4.190 

0 

329 

0 

50,537 

4,190 

0 

July 

2,560 

54,880 

2,560 

0 

387 

0 

48,919 

2,560 

0 

Aug 

2,210 

54,493 

2.210 

0 

.361 

0 

47,208 

2,210 

0 

Sept. 

1.820 

54,132 

1,820 

0 

278 

0 

45,531 

1,820 

0 

Oct. 

2,070 

53,854 

2,070 

0 

212 

0 

43.970 

2,070 

0 

Nov. 

1,960 

53,642 

1,960 

0 

J  39 

0 

42,432 

1,960 

0 

Doc. 
Total  or 
average 

2.870 

53,503 

2.870 

0 

0 

0 

41,000 

2,870 

0 

72.950 

56,444 

62,322 

2,245 

0 

56,4-14 

59.529 

THE    CONTROL   OF    FLOODS   BY   RESERVOIRS. 

RESERVOIR  ON  SAN  GABRIEL  RIVER. 

THREE  STEPS  IN  COORDINATING  THE 

ERVOIR  SPACE. 

tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  16,  page  182.) 


433 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights. 


1 

"lood  control  completely  coordinated  with  conservation 

coordinated  with  conservation      1 

Reservoi 

>■  emptied  each  summe 

I-  to  a  level  that  would  mamtain 

onstant 

feet  maintained,  other  drafts        | 

dra 

Ft  through  critical  peri 

od;  constant  draft  of  22 second-feet 

reservoir  operating  dia 

gram 

maintained,  other  drafts  only  as  required  by 

reservoir  operating  diagram 

Flood 
control 

Constant 
draft 
from 

Evapora- 
tion from 

Waste 

Stage  of 
reservoir 

Passed 

water 
passing 
Azusa 
during 

Constant 
draft 
from 

Variable 

summer 

draft 

Evapora- 
tion from 

Waste 

Year  and 
month 

over-year 
storage - 

(22 
second- 
feet)  in 
acre-feet 

reseri-oir 
surface 

in 
acre-feet 

over 
spillway 

in 
acre-feet 

at 
beginning 

of 
month  in 
acre-feet 

by  dam 
for  prior 
rights  in 
acre-feet 

flood 
season 
at  rates 
less 
than  1,900 
second- 
feet  in 
acre-feet 

over-yetr 
storage 

(•22 
second- 
feet)  in 

acre-feet 

from 

seasonally 

stored 

water  in 

acre  feet 

reservoir 
surface 

in 
acre-feet 

over 
spillway 

in 
acre-feet 

• 

1906 

1,352 

0 

0 

51,265 

3,633 

0 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

50,520 

3,960 

0 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

49,298 

7,561 

23,965 

1,352 

0 

0 

0 

Mar. 

1,.309 

381 

0 

145,420 

9,042 

15,432 

1,309 

13,028 

357 

0 

April 

1,352 

541 

0 

140.852 

9,344 

0 

1,352 

15,553 

498 

0 

May 

1,309 

674 

0 

135,105 

9,042 

0 

1,309 

17,843 

569 

0 

June 

1,352 

803 

0 

121,842 

8,664 

0 

1,.352 

20.527 

609 

0 

July 

1,352 

738 

0 

100,040 

4,490 

0 

1,352 

20,774 

488 

0 

.A.ug. 

1,309 

567 

0 

77,426 

2,840 

0 

1,309 

20,043 

315 

0 

Sept 

1,352 

430 

0 

55,759 

2,450 

0 

1,352 

'  0 

214 

0 

Oct. 

1,309 

286 

0 

54,193 

2,400 

0 

1,309 

0 

139 

0 

Nov. 

1,352 

0 

0 

52,745 

4,030 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 
average 

15,922 

4,420 

0 

67,456 

39,397 

15,922 

107,768 

3,189 

0 

1907 

1,352 

0 

0 

58,963 

9,217 

51,921 

1,-352 

0 

0 

0 

Jan. 

1,222 

0 

0 

54,873 

8,439 

29,904 

1,222 

0 

0 

0 

Feb. 

1,.352 

0 

0 

62,408 

9,344 

45,814 

1,3.52 

0 

0 

0 

Mar. 

1.309 

391 

0 

121,898 

9,042 

0 

1,309 

9,221 

375 

0 

April 

1,352 

585 

0 

160,351 

9,344 

0 

1,352 

19,487 

539 

0 

May 

1,309 

720 

3,351 

151,129 

9,042 

0 

1,309 

21,773 

609 

0 

June 

1,352 

847 

0 

133,496 

7,920 

0 

1,352 

24,466 

642 

0 

July 

1,352 

781 

0 

107,476 

5,390 

0 

1,352 

24.651 

462 

0 

Aug. 

1,309 

599 

0 

81,011 

3,580 

0 

1.309 

23,737 

321 

0 

Sept. 

1,352 

450 

0 

55,644 

4,090 

0 

1,.352 

0 

214 

0 

Oct. 

1,309 

254 

0 

54,078 

3,800 

0 

1,309 

0 

139 

0 

Nov. 

1,352 

0 

0 

52,630 

3,600 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 

15,922 

4,627 

3,351 

82,808 

127,639 

15.922 

123,335 

3,301 

0 

average 
1908 

1,352 

0 

0 

51,278 

4.973 

5,543 

1,352 

0 

0 

0 

Jan. 

1,265 

0 

0 

50,510 

8,741 

4,616 

1.265 

0 

0 

0 

Feb. 

1,352 

0 

0 

50,888 

9,255 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

196 

0 

52,981 

8,656 

0 

1,309 

0 

196 

0 

April 

1,352 

262 

0 

52,100 

7,139 

0 

1,352 

0 

202 

0 

May 

1,309 

309 

0 

50,537 

4,190 

0 

1,309 

0 

309 

0 

Jane 

1,352 

359 

0 

48,919 

2,560 

0 

1,352 

0 

359 

0 

July 

1,352 

325 

0 

47,208 

2,?10 

0 

1,352 

0 

325 

0 

Ajg. 

1.309 

252 

0 

45,531 

1,820 

0 

1,309 

0 

252 

0 

Sept. 

1,352 

186 

0 

43,970 

2,070 

0 

1,352 

0 

186 

0 

Oct. 

1,309 

123 

0 

42,432 

).960 

0 

1,309 

0 

123 

0 

Nov. 

1,352 

0 

0 

41,000 

2,870 

0 

1,352 

0 

0 

0 

D-'c. 

Total  or 
average 

15,965 

2,012 

0 

56,4441        10,159 

15,965J               0 

2,012 

0 

434 


WATER  RESOURCES   OF   CALIFORNIA. 


TABLE  16a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

USE  OF  RES 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 


Natural  flow  up  to  152  second- 

Flood  control  alone 

Flood  control  part'ally 

Water  drawn  from  reservoir  only  as  required  by 

Constant  draft  c 

f  22  second- 

reservoir  operating  diagram 

only  as 

required  by 

Flood 

Flood 

Run-off 

control 

control 

Year  and 
month 

at 

Azusa 

in 

acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 

rights  in 
acre-feet 

water 

passing 

AiUBa 

daring 

flood 

season 

at  rates 

less 

than  1,900 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 
spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 

passing 

Azusa 

during 

-  flood 

season 

at  rates 

less 

than  1.900 

« 

second- 
feet  in 
acre-feet 

second- 
feet  in 
acre-feet 

1909 

.Jan. 

2.i,500 

53,503 

5.596 

23,888 

0 

0 

39.648 

5,596 

8.681 

Feb. 

59,400 

49.519 

8,440 

42,858 

0 

0 

49.519 

8,440 

41.897 

Mar. 

26,.300 

57.621 

9.344 

0 

0 

0 

57.360 

9.344 

0 

April 

28,000 

74,577 

9,042 

0 

268 

0 

72,964 

9.042 

0 

May 

15,200 

93.267 

9,344 

0 

391 

0 

90,351 

9..344 

0 

June 

8,570 

98,732 

8,319 

0 

476 

0 

94,474 

8.319 

0 

July 

5.040 

98.507 

5,040 

0 

559 

0 

92,956 

5.040 

0 

Aug. 

3,120 

97.948 

3.120 

0 

520 

0 

91,067 

3.120 

0 

Sept. 

2,320 

97.428 

2.320 

0 

401 

0 

89,221 

2.320 

0 

Oct. 

2,310 

97.027 

2.310 

0 

305 

0 

87,535 

2.310 

0 

Nov. 

2,880 

96,722 

2.880 

0 

204 

0 

85,897 

2,880 

0 

Dec. 
Total  or 
average 

20,900 

96,518 

6.346 

38.233 

0 

0 

84,400 

6.346 

24.763 

199,540 

72.101 

104.979 

3,124 

0 

72.101 

75.341 

1910 

Jan. 

69,500 

72,839 

9.344 

82.868 

0 

0 

72,839 

9.344 

81.516 

Feb. 

11,500 

50,127 

8,435 

2,689 

0 

0 

50,127 

8,435 

2,292 

Mar. 

9,590 

50,503 

9.029 

0 

0 

0 

49,678 

9,029 

0 

April 

8,270 

51,0f)4 

8,120 

0 

190 

0 

48,887 

8.120 

0 

May 

5,050 

51,024 

5.050 

0 

262 

0 

47,542 

5,050 

0 

June 

3,560 

50,702 

3.560 

0 

311 

0 

45,940 

3,560 

0 

July 

2,450 

50.451 

2.450 

0 

369 

0 

44,340 

2,450 

0 

Aug. 

1,710 

50.082 

1.710 

0 

341 

0 

42.651 

1,710 

0 

Sept. 

1,370 

49.741 

1.370 

0 

264 

0 

40.992 

1,370 

0 

Oct. 

1,560 

49.477 

1.560 

0 

202 

0 

39.449 

1,560 

0 

Nov. 

1,870 

49.275 

1.870 

0 

133 

0 

37,923 

1.870 

0 

Dec. 
Total  or 
average 

2,020 

49.142 

2.020 

0 

0 

0 

36,501 

2.020 

0 

118,450 

54.518 

85.557 

2.072 

0 

54.518 

83.808 

1911 

Jan. 

37,200 

49,142 

6.441 

7,031 

0 

0 

35.149 

6,441 

6.949 

Feb. 

44.300 

72.870 

8.440 

.54,016 

0 

0 

57.607 

8.440 

38.010 

Mar. 

122,000 

54.714 

9.344 

57,434 

0 

0 

54.235 

9,344 

55.857 

April 
May 

28.200 

109,936 

9.042 

0 

335 

0 

109.682 

9.042 

0 

16.600 

128.759 

9,344 

0 

482 

0 

127.196 

9.344 

0 

June 

7.500 

135.,533 

7,,322 

0 

589 

0 

132.622 

7.322 

0 

July 

5.230 

135.122 

5,230 

0 

696 

0 

130.912 

5.230 

0 

Aug. 

3.610 

134,426 

3,610 

0 

644 

0 

128.884 

3.610 

0 

Sept. 

2.830 

133,782 

2,830 

0 

498 

0 

126.909 

2.830 

0 

Oct. 

3.140 

133.284 

3,140 

0 

379 

0 

12.5,124 

3.140 

0 

Nov. 

2.800 

132.905 

2,800 

11.766 

248 

0 

123.411 

2.800 

1.061 

Dec. 
Total  or 
average 

2.870 

120,891 

2,870 

2.3.312 

0 

0 

120,803 

2.870 

22,352 

276.280 

70,413 

153.559 

3,871 

0 

70.413 

124,229 

THE   CONTROL   OP   FLOODS   BY   RESERVOIRS, 


435 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 


THREE  STEPS  IN  COORDINATING  THE 

ERVOIR  SPACE. 

tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  16,  page  182.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights. 


'lood  control  completely  coordinated  with  conservation 

coordinated  with  conservation 

Reservoir  emptied  each  summer  to  a  level  that  would 

mamtam  constant 

feet  maintained,  other  drafts 

draft  through 

ritical  period;  constant  draft  of  2 

2  second-feet 

reservoir  operating  diagram 

maintained,  other  drafts  only  as  required  by 

reservoir  operating  diagram 

Flood 

control 

Constant 

draft 

from 

over-year 

storage 

(22 
second- 
feet)  in 
acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 
passing 
Azusa 
during 
flood 
season 
at  rates 
less 
than  1,900 
second- 
feet  in 
acre-feet 

Constant 

draft 

from 

over-year 

storage 

(22 
second- 
feet)  in 
acre-feet 

Variable 

summer 

draft 

from 

seasonally 

stored 

water  in 

acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Year  and 
month 

1909 

1,352 

0 

0 

39,648 

5,596 

8,681 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

49,519 

8,440 

41,897 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

57,360 

9,344 

0 

1,353 

0 

0 

0 

Mar. 

1,309 

262 

0 

72,964 

9,042 

0 

1,309 

1,190 

258 

0 

April 

1,352 

381 

0 

89,165 

9,344 

0 

1,352 

5,041 

369 

0 

May 

1,309 

460 

0 

88,259 

8,319 

0 

1,309 

6,306 

428 

0 

June 

1,352 

537 

0 

80,467 

5,040 

0 

1,352 

6,639 

478 

0 

July 

1,352 

494 

0 

71,998 

3,120 

0 

1,352 

6,578 

412 

0 

Aug. 

1,309 

377 

0 

63,656 

2,320 

0 

1,309 

6,365 

295 

0 

Sept. 

1,352 

286 

0 

55,687 

2,310 

0 

1,352 

0 

214 

0 

Oct. 

1,309 

188 

0 

54,121 

2.R80 

0 

1,309 

0 

139 

0 

Nov. 

1,352 

0 

0 

52,673 

6,346 

1,682 

1,352 

0 

0 

0 

Dec. 
Total  or 
average 

15,922 

2,985 

72,101 

52,260 

15,922 

32,119 

2,593 

0 

1910 

1,352 

0 

0 

64,193 

9,344 

72,870 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

50,127 

8,435 

2,292 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

49,678 

9,029 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

186 

0 

48,887 

8,120 

0 

1,309 

0 

186 

0 

April 

1,352 

250 

0 

47,542 

5,050 

0 

1,352 

0 

250 

0 

May 

1,309 

291 

0 

45,940 

3,.560 

0 

1,309 

0 

291 

0 

June 

1,352 

337 

0 

44,340 

2,450 

0 

1,352 

0 

337 

0 

July 

1,352 

307 

0 

42,651 

1,710 

0 

1,352 

0 

307 

0 

Aug. 

1,309 

234 

0 

40,992 

1,370 

0 

1,309 

0 

234 

0 

Sept. 

1,352 

174 

0 

39,449 

1,560 

0 

1,352 

0 

174 

0 

Oct. 

1,309 

113 

0 

37,923 

1,870 

0 

1,309 

0 

113 

0 

Nov. 

1,352 

0 

0 

36,501 

2,020 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 

15,922 

1,892 

0 

54,518 

75,162 

15,922 

0 

1,892 

0 

average 
1911 

1,352 

0 

0 

35,149 

6,441 

6,949 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

57,607 

8,440 

38,010 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

54,235 

9,344 

55,857 

1,3.52 

0 

0 

0 

Mar. 

1,309 

335 

0 

109,682 

9,012 

0 

1,309 

7,198 

325 

0 

April 

1,352 

478 

0 

120,008 

9,344 

0 

1,352 

11,311 

446 

0 

May 

1,309 

579 

0 

114,155 

7,322 

0 

1,309 

12,671 

502 

0 

June 

1,352 

676 

0 

99,851 

5,230 

0 

1,352 

13.155 

537 

0 

July 

1,352 

623 

0 

84,807 

3,610 

0 

1,352 

13,094 

446 

0 

Aug. 

1,309 

476 

0 

69,915 

2,830 

0 

1,309 

12,612 

306 

0 

Sept. 

1,352 

361 

0 

55,688 

3,140 

0 

1,352 

0 

215 

0 

Oct. 

1,309 

238 

0 

,'54,121 

2,800 

0 

1,309 

0 

139 

0 

Nov. 

1,352 

0 

0 

52,673 

2,870 

0 

1,.352 

0 

0 

0 

Dec. 
Total  or 

15,922 

3,766 

c 

70,413 

100,816 

15,922 

70,041 

2,916 

0 

average 

436 


WATER  RESOURCES   OF   CALIFORNIA. 


TABLE  16a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

USE  OF  RES 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 


Natural  flow  up  to  152  second- 

Flood  control  alone 

Flood  control  partially 

Wate 

r  drawn  from  reservoir  oi 

ly  as  required  by 

Constant  draft  o 

f  22  second- 

reservoir  operating  diagram 

only  as  reriuired  by 

Flood 

Flood 

Run-off 

control 

control 

Year  and 

month 

at 

Azusa 

in 

Stage  of 
reservoir 

Passed 

water 
passing 

Azusa 
during 

flood 
season 
at  rates 

less 
than  1,900 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

Stage  of 
reservoir 

Passed 

water 

passing 

Aztisa 

during 

flood 

season 

at  rates 

less 

than  1,900 

acre-feet 

at 
beginning 

of 
month  in 
acre-feet 

by  dam 
for  prior 
rights  in 
acre-feet 

over 
spillway 

in 
acre-feet 

at 
beginning 

of 
month  in 
acre-feet 

by  dam 
for  prior 
rights  in 
acre-feet 

second- 

second- 

feet  in 

feet  in 

acre-feet 

acre-feet 

1912 

Jan. 

2,710 

97,579 

2,710 

0 

0 

0 

97,099 

2,710 

0 

Feb. 

2,230 

97,579 

2,230 

0 

0 

0 

95,747 

2,230 

0 

Mar. 

22,!»00 

97,579 

8,199 

3,590 

0 

0 

94,482 

8,199 

496 

April 

18,000 

108,690 

8,515 

0 

319 

0 

107,335 

8,515 

0 

May 

10,900 

117,856 

8,828 

0 

454 

0 

115,196 

8.828 

0 

June 

4,990 

119,474 

4,990 

0 

539 

0 

11.5,474 

4,990 

0 

July 

,3,060 

118,935 

3,060 

0 

637 

0 

113,040 

3,060 

0 

Aug. 

1,960 

118,298 

1,960 

0 

591 

0 

111,675 

1,960 

0 

Sept. 

1,5.50 

117,707 

1,550 

0 

454 

0 

109,7.58 

1,5.50 

0 

Oct. 

1,8.30 

117,253 

1,830 

0 

347 

0 

108,019 

1,830 

0 

Nov. 

1,7.30 

116,906 

1,730 

0 

232 

0 

106,340 

1,730 

0 

Dec. 
Total  or 
average 

1,700 

116,674 

1,700 

7.665 

0 

0 

104,815 

1,760 

0 

73,620 

47,362 

11,255 

3,573 

0 

47,362 

496 

1913 

Jan. 

2,910 

109,009 

2,910 

8,725 

0 

0 

103,463 

2,910 

4,136 

Feb. 

13,200 

100,284 

4,753 

27,773 

0 

0 

97,975 

4,753 

24,767 

Mar. 

10,200 

80,058 

8,759 

11,336 

0 

0 

80,433 

8,759 

10,660 

April 

7,110 

71,003 

7,091 

0 

238 

0 

69,862 

7,091 

0 

May 

4,970 

70,874 

4,970 

0 

319 

0 

68,370 

4,970 

0 

June 

2,890 

70,555 

2,890 

0 

385 

0 

66,709 

2,890 

0 

July 

1,690 

70,170 

1,690 

0 

452 

0 

65,033 

1,690 

0 

Aug. 

1,070 

69,718 

1,070 

0 

418 

0 

63,255 

1,070 

0 

Sept. 

893 

69,300 

893 

0 

323 

0 

61,512 

893 

0 

Oct. 

910 

68,977 

910 

0 

246 

0 

59,906 

910 

0 

Nov. 

2,280 

68,731 

2,280 

0 

165 

0 

58,330 

2,280 

0 

Dec. 

2,170 

68,566 

2,170 

0 

0 

0 

56,874 

2,170 

0 

Total  or 
average 

60,323 

40,386 

47,834 

2.546 

0 

40,386 

39.563 

1914 

Jan. 

01,400 

68,566 

6,271 

56,127 

0 

0 

55,522 

6,271 

47,159 

Feb. 

121,000 

67,568 

8,440 

64,933 

0 

0 

62,140 

8,440 

58,284 

Mar. 

48,000 

11.5,195 

9,344 

53,083 

0 

0 

115,194 

9,344 

52,388 

April 
Niay 

21,400 

100,768 

9,042 

0 

307 

0 

100,110 

9,042 

0 

16,900 

112,819 

9,344 

0 

430 

0 

110,854 

9,344 

0 

June 

9,580 

119,945 

8,585 

0 

535 

0 

116,630 

8,,585 

0 

July 

5,570 

120,405 

5,570 

0 

641 

0 

115,786 

5,570 

0 

Aug. 

3,630 

119,704 

3,630 

0 

595 

0 

113,803 

3,630 

0 

Sept. 

2,730 

119,169 

2,730 

0 

4.58 

0 

111,879 

2,730 

0 

Oct. 

2,770 

118,711 

2.770 

0 

349 

0 

110,134 

2,770 

0 

Nov. 

2,440 

118,362 

2,440 

0 

234 

0 

108,451 

2,440 

0 

Dec. 

4,290 

118,128 

4,290 

53,539 

0 

0 

106,922 

4,290 

40.981 

Total  or 
average 

299,710 

72,450 

227,682 

3,549 

0 

72,456 

198,812 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


437 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

THREE  STEPS  IN  COORDINATING  THE 

ERVOIR  SPACE. 

tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  16,  page  182.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for 

prior  rights. 

1 

-lood  control  completely  coordinated  with  conservation 

1 

coordinated  with  conservation 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant     | 

feet  maintained,  other  drafts 

draft  through 

:ritical  period;  constant  draft  of  22  second-feet 

reservoir  operating  dia 

?ram 

maintained,  other  drafts  only  as  required  by 

reservoir  operatmg  diagram 

Flood 

control 

Constant 
draft 
from 

Evapora- 
tion from 

Waste 

Stage  of 
reservoir 

Passed 

water 
passing 
Azusa 
during 

Constant 
draft 
from 

Variable 

summer 

draft 

Evapora- 
tion from 

Waste 

Year  and 
month 

over-year 

storage 

(22 
second- 
feet)  in 
acre-feet 

reservoir 
surface 

in 
acre-feet 

over 

spillway 

in 
acre-feet 

at 
beginning 

of 
month  in 
aere-feet 

by  dam 
for  prior 
rights  in 
acre-feet 

flood 
season 
at  rates 

less 
than  1,900 
second- 
feet  in 
acre-feet 

over-year 
storage 

(22 
second- 
feet)  in 

acre-feet 

from 

seasonally 

stored 

water  in 

acre-feet 

reservoir 
surface 

in 
acre-feet 

over 
spillway 

in 
acre-feet 

1912 

1,352 

0 

0 

51,321 

2,710 

0 

1,352 

0 

0 

0 

Jan. 

1,265 

0 

0 

49,969 

2,230 

0 

1,265 

0 

0 

0 

Feb. 

1,352 

0 

0 

48,704 

8,199 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

315 

0 

62,053 

8,515 

0 

1,309 

0 

238 

0 

April 

1,352 

442 

0 

69,991 

8,828 

0 

1,352 

1,168 

315 

0 

May 

1,309 

525 

0 

69,228 

4,990 

0 

1,309 

1,606 

373 

0 

June 

1,352 

613 

0 

65,940 

3,060 

0 

1,352 

1,660 

426 

0 

July 

1,352 

565 

0 

62,502 

1,960 

0 

1,352 

1,660 

359 

0 

Aug. 

1,309 

430 

0 

69,131 

1,550 

0 

1,309 

1.667 

291 

0 

Sept. 

1,352 

327 

0 

55,864 

1,830 

0 

1,352 

0 

215 

0 

Oct. 

1,309 

216 

0 

54,297 

1,730 

0 

1,309 

0 

139 

0 

Nov. 

1,352 

0 

0 

52,849 

1,760 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 

15,965 

3,433 

0 

47,362 

0 

15,965 

7,761 

2,356 

0 

average 
1913 

1,352 

0 

0 

51,497 

2,910 

0 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

50,145 

4,753 

0 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

57,370 

8,759 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

232 

0 

57,459 

7,091 

0 

1,309 

0 

206 

0 

April 

1,352 

309 

0 

55,993 

4,970 

0 

1,352 

0 

27'' 

0 

May 

1,309 

367 

0 

54,367 

2,890 

0 

1,309 

0 

321 

0 

June 

1,352 

426 

0 

52,737 

1,690 

0 

1,352 

0 

375 

0 

July 

1,352 

391 

0 

51,010 

1,070 

0 

1,352 

0 

340 

0 

Aug. 

1,309 

297 

0 

49,318 

893 

0 

1,309 

0 

260 

0 

Sept. 

1,352 

224 

0 

47,749 

910 

0 

1,352 

0 

196 

0 

Oct. 

1,309 

147 

0 

46,201 

2,280 

0 

1,309 

0 

127 

0 

Nov. 

1,352 

0 

0 

44,765 

2,170 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 

15,922 

2,393 

0 

40,386 

0 

15,922 

0 

2,099 

0 

average 
1914 

1,352 

0 

0 

43,413 

6,271 

35,050 

1.352 

0 

0 

0 

Jan. 

1,222 

0 

0 

62,140 

8,440 

58,284 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

115,194 

9,344 

52,388 

1,352 

0 

0 

0 

Mar. 

1,309 

305 

0 

109,110 

9,042 

0 

1,309 

5,652 

301 

0 

April 

1,352 

428 

0 

105,206 

9,344 

0 

1,352 

8,299 

410 

0 

May 

1,309 

530 

0 

102,701 

8,585 

0 

1,309 

9,875 

472 

0 

June 

1,352 

631 

0 

92,040 

5,570 

0 

1,352 

10,512 

516 

0 

July 

1,352 

572 

0 

79,660 

3,630 

0 

1,352 

10,450 

432 

0 

Aug. 

1,309 

436 

0 

67,426 

2,730 

0 

1,309 

10,113 

301 

0 

Sept. 

1,352 

331 

0 

55,703 

2,770 

0 

1,352 

0 

214 

0 

Oct. 

1,309 

220 

0 

54,137 

2,440 

0 

1,309 

0 

139 

0 

Nov. 

1,352 

0 

0 

52,689 

4,290 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 

15,922 

3,453 

0 

72,456 

145,722 

15,922 

54,901 

2,785 

0 

average 

438 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  16a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

USE  OF  RES 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 


Natural  flow  up  to  152  second- 


Flood  control  alone 

Flood  con 

trol  partially 

Water  drawn  from  reservoir  only  as  required  by 

Constant  draft  c 

f  22  second- 

reser\'oir  operating  diagram 

only  as  required  by 

Flood 

Flood 

Run-off 

control 

control 

Year  and 
month 

at 

Azusa 

in 

Stage  of 

water 
passing 
Azusa 

Evapora- 

Waste 

Stage  of 

Passed 

water 
passing 
Azusa 

acre-feet 

r3S8rvoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 

during 

tion  from 

reser\-oir 

at 
beginning 

of 
month  in 
acre-feet 

ty  dam 

during 

by  dam 
for  prior 

flood 
season 

reservoir 
surface 

over 
spillway 

for  prior 
rights  in 

flood 
season 

rights  in 
acre-feet 

at  rates 

less 

than  1,900 

in 
acre-feet 

acre-feet 

acre-feet 

at  rates 

less 

than  1,900 

second- 

second- 

feet  in 

feet  in 

acre-feet 

acre-feet 

1915 

Jan. 

7,380 

64,5S9 

4,428 

9,932 

0 

0 

64.589 

4,428 

8,659 

Feb. 

30,200 

57,609 

8,412 

21,485 

0 

0 

57.530 

8,412 

20,577 

Mar. 

21,500 

57,912 

9,344 

0 

0 

0 

57,519 

9.344 

0 

.\pril 

17,300 

70,068 

9,042 

0 

238 

0 

68,323 

9.042 

0 

May 

20,400 

78.088 

9,344 

0 

369 

0 

75,034 

9,344 

0 

June 

11,400 

88,775 

8,967 

0 

476 

0 

84,395 

8,967 

0 

Joly 

7,010 

90,732 

7,010 

0 

529 

0 

85.085 

7,010 

0 

Aug. 

3,980 

90,203 

3,980 

0 

492 

0 

83,225 

3,980 

0 

Sept. 

3,270 

89,711 

3,270 

0 

381 

0 

81,409 

3,270 

0 

Oct. 

2,770 

89,330 

2,770 

0 

290 

0 

79,745 

2,770 

0 

Nov. 

3,010 

89,040 

3,010 
3,o80 

0 

192 

0 

78,125 

3,010 

0 

Dec. 

3,580 

88,848 

0 

0 

0 

76.640 

3.580 

0 

Total  or 
average 

131,800 

73,157 

31,417 

2,967 

0 

73.157 

29,236 

1916 

Jan. 

148,000 

88,848 

8,759 

85.470 

0 

0 

75,288 

8,759 

70,558 

Feb. 

30,400 

142,619 

8,741 

101,672 

0 

0 

142,619 

8.741 

100.407 

Mar. 

34,800 

71,600 

9,344 

4,852 

0 

0 

71.606 

9.344 

4.679 

.\pril 

l'j,',i00 

92,210 

9,042 

0 

297 

0 

91,031 

9.042 

0 

May 

10,400 

102,771 

9,130 

0 

430 

0 

100,292 

9,130 

0 

June 

5,830 

103,611 

5,830 

0 

492 

0 

99,811 

5,830 

0 

July 

4,770 

103,119 

4,770 

0 

577 

0 

98,026 

4.770 

0 

Aug. 

3,570 

102,542 

3,570 

0 

535 

0 

96.119 

3,570 

0 

Sept. 

2,810 

102,007 

2.810 

0 

412 

0 

94.255 

2,810 

0 

Oct. 

7,010 

101,595 

6,473 

0 

307 

0 

92,555 

6.473 

0 

Nov. 

4,130 

101,825 

4,130 

0 

212 

0 

91,445 

4,130 

0 

Dec. 

13,600 

101,613 

5,253 

46,759 

0 

0 

89,940 

5,253 

33,734 

Total  or 
average 

294,220 

77.852 

238,753 

3,262 

0 

77.852 

209,378 

1917 

Jan. 

9,280 

63,201 

8,172 

14,791 

0 

0 

63,201 

8,172 

13,501 

Feb. 

13.2(K) 

49,518 

7,551 

0 

0 

0 

49,456 

7,551 

0 

Mar. 

13,800 

55,167 

9,344 

0 

0 

0 

53,883 

9,344 

0 

April 
May 

10,500 

59.423 

9,042 

0 

212 

0 

56.787 

9,042 

0 

8,610 

60.669 

8,531 

0 

288 

0 

56.728 

8.531 

0 

June 

5,270 

60.460 

5.270 

0 

347 

0 

55.179 

5.270 

0 

July. 

.3,140 

60,113 

3,140 

0 

410 

0 

53,543 

3,140 

0 

Aug. 

2,200 

59,703 

2,200 

0. 

379 

0 

51,812 

2,200 

0 

Sept. 

1,510 

59,324 

1,510 

0 

293 

0 

50.115 

1.510 

0 

Oct. 

1,560 

59,031 

1,560 

0 

224 

0 

48,544 

1,560 

0 

Nov. 

1,840 

5?,807 

1,840 

0 

149 

0 

46,994 

1.840 

0 

Dec. 

2,000 

58.658 

2,000 

0 

0 

0 

45.558 

P.OOO 

0 

Total  or 
average 

72710 

60,160 

14.791 

2,302 

0 

60,160 

13,501 

THE    CONTROL   OP    FLOODS   BY   RESERVOIRS. 


439 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

THREE  STEPS  IN  COORDINATING  THE 

ERVOIR  SPACE. 

tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  16,  page  182.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for 

'prior'rights. 

1 

^lood  control  completely  coordinated  with  conservation 

coordinated  with  conservation      | 

Reserve 

r  emptied  each  summer  to  a  level  that  wouk 

maintain  constant 

eet  maintained,  other 

drafts 

draft  through 

critical  period;  constant  draft  of  22  second-feet 

eservoir  operating  diagram          | 

maintained,  otherdrafts  only  as  requir 

=dby 

reservoir  operating  diagram 

Flood 

control 

Constant 

draft 

from 

over-year 

storage 

(22 
second- 
feet)  in 
acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 
passing 
Aausa 
during 
flood 
season 
at  rates 
less 
than  1,900 
second- 
feet  in 
acre-feet 

Constant 

draft 

from 

over-year 

storage 

(22 
second- 
feet)  in 
acre-feet 

Variable 

summer 

draft 

from 

seasonally 

stored 

water  in 

acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Year  and 
month 

1915 

1,352 

0 

0 

51,337 

4,428 

3,629 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

49,308 

8,412 

12,355 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

57,519 

9,344 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

238 

0 

68,323 

9,042 

0 

1,309 

416 

238 

0 

Apr=l 

1,352 

343 

0 

74,618 

9,344 

0 

1,352 

2,090 

341 

0 

May 

1,309 

434 

0 

81,891 

8,967 

0 

1,309 

4,759 

414 

0 

June 

1,352 

508 

0 

77,842 

7,010 

0 

1,352 

5,717 

468 

0 

July 

1,352 

464 

0 

70,305 

3,989 

0 

1,352 

5,717 

407 

0 

Aug. 

1,309 

355 

0 

62,829 

3,270 

0 

1.309 

5,533 

293 

0 

Sept. 

1,352 

268 

0 

55,694 

2,770 

0 

1,352 

0 

214 

0 

Oct. 

1,309 

176 

0 

54,128 

3,010 

0 

1,309 

0 

139 

0 

Nov. 

1,352 

0 

0 

52,680 

3,580 

0 

1,352 

0 

0 

0 

Dec. 

Total  or 
average 

15,922 

2,786 

0 

73,157 

15,984 

15,922 

24,232 

2,514 

0 

1916 

1,352 

0 

0 

51,328 

8,759 

51,935 

1,352 

0 

0 

0 

,Ian. 

1,265 

0 

0 

137,282 

8,741 

99,779 

1,265 

0 

0 

0 

Feb. 

1,352 

0 

0 

66,897 

9,344 

603 

1,352 

0 

0 

0 

Mar. 

1,309 

288 

0 

90,398 

9,042 

0 

1,309 

4,045 

284 

0 

April 

1,352 

399 

0 

95,618 

9,130 

0 

1,352 

6,393 

379 

0 

May 

1,309 

476 

0 

88,764 

5,830 

0 

1,309 

6,484 

430 

0 

June 

1,352 

555 

0 

80,541 

4,770 

0 

1,352 

6,639 

480 

0 

July 

1,352 

512 

0 

72,070 

3,570 

0 

1,352 

6,639 

412 

0 

Aug. 

1,309 

391 

0 

63,667 

2,810 

0 

1,309 

6,425 

295 

0 

Sept. 

1,352 

295 

0 

55,638 

6,473 

0 

1,352 

0 

214 

0 

Oct. 

1,309 

196 

0 

54,609 

4,130 

0 

1,309 

0 

131 

0 

Nov. 

1,352 

0 

0 

53,169 

5,253 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 
average 

15,965 

3,112 

0 

77,852 

152,317 

15,965 

36,625 

2,625 

0 

1917 

1,352 

0 

0 

60,104 

8,172 

10,464 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

49,456 

7,551 

0 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

53,883 

9,344 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

208 

0 

56,787 

9,042 

0 

1,309 

0 

208 

0 

April 

1,352 

276 

0 

56,728 

8,531 

0 

1,352 

0 

276 

0 

May 

1,309 

327 

0 

55,179 

5,270 

0 

1,309 

0 

327 

0 

June 

1,352 

379 

0 

53,543 

3,140 

0 

1,352 

0 

379 

0 

July 

1,352 

345 

0 

51,812 

2,200 

0 

1,352 

0 

345 

0 

Aug. 

1,309 

262 

0 

50,115 

1,510 

0 

1,309 

0 

262 

0 

Sept. 

1,352 

198 

0 

48,544 

1,560 

0 

1,352 

0 

198 

0 

Oct. 

1,309 

127 

0 

46,994 

1.840 

0 

1,309 

0 

127 

0 

Nov. 

1,352 

0 

0 

45,558 

2,000 

0 

1,352 

0 

0 

0 

Dec. 

1 

Total  or 
average 

15,922 

2,122 

0 

60,160 

10,464 

15,922|               0 

2,122 

0 

440 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  16a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

USE  OF  RES 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 


Natural  flow  up  to  152  second- 


Flood  control  alone 

Flood  control  partially 

Wate 

r  drawn  fron: 

reservoir  only  as  required  by 

Constant  draft  0 

f  22  second- 

reservoir  operating  diagram 

only  as 

required  by 

Flood 

Flood 

Run-off 

control 

control 

Year  and 
month 

at 

Azusa 

in 

acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 
passing 
Azusa 
during 
flood 
season 
at  rates 
less 

than  1,900 
second- 
feet  in 

acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 
passing 
.\zu8a 
during 
flood 
season 
at  rates 
less 
than  1,900 
second- 
feet  in 
acre-feet 

1918 

Jan. 

2,020 

58,658 

2,020 

0 

0 

0 

44,206 

2,020 

0 

Feb. 

9,330 

58,658 

3,847 

0 

0 

0 

42,854 

3,847 

0 

Mar. 

73,200 

64,141 

9,249 

19,393 

0 

0 

47,115 

9,249 

3,595 

April 

17.000 

108,699 

9.042 

0 

321 

0 

106,119 

9.042 

0 

May 

10,000 

11(),336 

8,993 

0 

444 

0 

112,453 

8,993 

0 

June 

6,010 

116,899 

6,010 

0 

531 

0 

111,672 

6,010 

0 

July 

3,970 

116,368 

3,970 

0 

627 

0 

109,849 

3.970 

0 

.•Vug. 

2,840 

115,741 

2,840 

0 

581 

0 

107,896 

2,840 

0 

Sept. 

2,330 

115,I()0 

2,330 

0 

446 

0 

105,993 

2.330 

0 

Oct. 

2,930 

114,714 

2,930 

0 

341 

0 

104,264 

2,930 

0 

Nov. 

3,140 

114,373 

3,140 

11,869 

238 

0 

102,593 

3,140 

0 

Dec. 

Total  or 
average 

4,370 

102,266 

4,370 

29,745 

0 

0 

101,072 

4,370 

27,459 

137,140 

58,741 

61,007 

3.529 

0 

58,741 

31,054 

1919 

Jan. 

3,3(10 

72,,521 

3,300 

0 

0 

(1 

72,261 

3,300 

0 

I'cl.. 

4,110 

72,521 

4,110 

0 

0 

(1 

70,909 

4,110 

0 

Mar. 

(1,110 

72,521 

6,110 

0 

0 

0 

69,687 

6,110 

0 

April 

(i,()10 

72„'->21 

6,010 

0 

238 

0 

68,335 

6,010 

0 

May 

3,810 

72,283 

3,810 

0 

323 

0 

66,796 

3,810 

0 

June 

1,890 

71,960 

1,890 

0 

.387 

0 

65,139 

1,890 

0 

July 

1,320 

71, .573 

1,320 

0 

458 

(1 

63,469 

1,320 

0 

Aug. 

93,') 

71,115 

935 

0 

422 

0 

61,697 

935 

0 

Sept. 

1,010 

70,693 

1,010 

0 

327 

0 

59,960 

1,010 

0 

Oct. 

2,040 

70,306 

2,040 

0 

248 

0 

58,358 

2,040 

0 

Nov. 

2.130 

70,118 

2.130 

0 

165 

0 

56,784 

2,130 

0 

Dec. 
Total  or 
average 

5.340 

09.953 

5,209 

7.081 

0 

0 

55,332 

5,209 

0 

38,005 

37,874 

7.081 

2,568 

0 

37,874 

0 

1920 

Jan. 

3,2()0 

63,003 

3,260 

8.130 

0 

0 

54,111 

3,260 

0 

Feb 

12,700 

54,873 

5.854 

885 

0 

0 

52,759 

5,854 

0 

Mar. 

3fi,200 

60,834 

9,344 

1,148 

0 

t) 

58,340 

9,344 

0 

April 
May 

25,100 

86,542 

9.042 

0 

288 

0 

83,844 

9.042 

0 

12,600 

102,312 

9.344 

0 

410 

0 

98,309 

9,344 

0 

June 

7,380 

105,1.58 

7.349 

0 

494 

0 

99,812 

7..349 

0 

July 

4,670 

104,695 

4.670 

0 

583 

0 

98,058 

4.670 

0 

Aug. 

3,200 

104,112 

3.200 

0 

541 

0 

96,151 

3.200 

0 

Sept. 

2,030 

103,571 

2.030 

0 

416 

0 

94,287 

2.030 

0 

Oct. 

2,000 

103,155 

2.000 

0 

317 

0 

92,587 

2.000 

0 

Nov. 

2,380 

102.838 

2.380 

358 

214 

0 

90,940 

2,380 

0 

Deo. 
Total  or 
average 

2,210 

102,266 

2.210 

30.538 

0 

0 

89,437 

2,210 

16,619 

113,730 

60,683 

41.059 

3,263 

0 

60,683 

16,619 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


441 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

THREE  STEPS  IN  COORDINATING  THE 

ERVOIR  SPACE. 

tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  16,  page  182.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights. 


Flood  control  completely  coordinated  with  conservation 

coordinated  with  conservation 

Reservoir  emptied 

;ach  Slimmer  to  a  level  that  would  maintam 

3onstant 

Jeet  maintained,  other 

drafts 

draft  through  critical  period;  constant  draft  of  22  second-feet 

reservoir  operating  diagram 

maintained,  othe 

r  drafts  only  as  required  by 

reservoir 

operating  diagram 

Flood 

control 

Constant 
draft 
from 

Evapora- 
tion from 

Waste 

Stage  of 
reservoir 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 
passing 
Azusa 
during 

Constant 
draft 
from 

Variable 

summer 

draft 

Evapora- 
tion from 

Waste 

Year  and 
month 

over-year 
storage 

(22 
second- 
feet)  in 

acre-feet 

reservoir 
surface 

in 
acre-feet 

over 

spillway 

in 
acre-feet 

at 
beginning 

of 
month  in 
acre-feet 

flood 

season 

at  rates 

less 

than  1,900 

second- 

over-year 
storage 

(22 
second- 
feet)  in 

acre-feet 

from 

seasonally 

stored 

water  in 

acre-feet 

reservoir 
surface 

in 
acre-feet 

over 

spillway 

in 
acre-feet 

feet  in 

acre-feet 

1918 

1,352 

0 

0 

44,206 

2,020 

0 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

42,854 

3,847 

0 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

47,115 

9,249 

3,595 

1,352 

0 

0 

0 

Mar. 

1,309 

315 

0 

106,119 

9,042 

0 

1,309 

6,603 

307 

0 

April 

1,352 

436 

0 

105,858 

8,993 

0 

1,352 

8,422 

412 

0 

May 

1,309 

514 

0 

96,679 

6,010 

0 

1,309 

8,388 

454 

0 

June 

1,352 

601 

0 

86,528 

3,970 

0 

1,352 

8,668 

496 

0 

July 

1,352 

551 

0 

76,012 

2,840 

0 

1,352 

8,606 

422 

0 

Aug. 

1,309 

420 

0 

65,632 

2,330 

0 

1,309 

8,329 

297 

0 

Sept. 

1,352 

319 

0 

55,697 

2,930 

0 

1,352 

0 

214 

0 

Oct. 

1,309 

212 

0 

54,131 

3,140 

0 

1,309 

0 

139 

0 

Nov. 

1,352 

0 

0 

52,683 

4,370 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 
average 

15,922 

3,368 

0 

58,741 

3,595 

15,922 

49,016 

2,741 

0 

1919 

1,352 

0 

0 

51,331 

3,300 

0 

1,352 

0 

0 

0 

Jan. 

1,222 

0 

0 

49,979 

4,110 

0 

1,222 

0 

0 

0 

Feb. 

1,352 

0 

0 

48,757 

6,110 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

230 

0 

47,405 

6,010 

0 

1,309 

0 

182 

0 

April 

1,352 

305 

0 

45,914 

3,810 

0 

1,352 

0 

244 

0 

May 

1,309 

361 

0 

44,318 

1,890 

0 

1,309 

0 

284 

0 

June 

1,352 

420 

0 

42,725 

1,320 

0 

1,352 

0 

329 

0 

July 

1,352 

385 

0 

41,044 

935 

0 

1,352 

0 

299 

0 

Aug. 

1,309 

293 

0 

39,393 

1,010 

0 

1,309 

0 

230 

0 

Sept. 

1,352 

222 

0 

37,854 

2,040 

0 

1,352 

0 

171 

0 

Oct. 

1,309 

143 

0 

36,331 

2,130 

0 

1,309 

0 

109 

0 

Nov. 

1.352 

0 

0 

34,913 

5,209 

0 

1,352 

0 

0 

0 

Dec. 

Total  or 
average 

15,922 

2,359 

0 

37,874 

0 

15,922 

0 

1,848 

0 

1920 

1,352 

0 

0 

33,692 

3,260 

0 

1,352 

0 

0 

0 

Jan. 

1,266 

0 

0 

32,340 

5,854 

0 

1,265 

0 

n 

0 

Feb. 

1,352 

0 

0 

37,921 

9,344 

0 

1,352 

0 

0 

0 

Mar. 

1,309 

284 

0 

63,425 

9,042 

0 

1,309 

0 

236 

0 

April 

1,352 

401 

0 

77,938 

9,344 

0 

1,352 

2,766 

339 

0 

May 

1,309 

476 

0 

76,737 

7,349 

0 

1,309 

3,510 

395 

0 

June 

1,352 

555 

0 

71,554 

4,670 

0 

1,352 

3,565 

446 

0 

July 

1,352 

512 

0 

66,191 

3,200 

0 

1,352 

3,627 

395 

0 

Aug 

1,309 

391 

0 

60.817 

2,030 

0 

1,309 

3,510 

290 

0 

Sept. 

1,352 

295 

0 

55,708 

2,000 

0 

1,352 

0 

214 

0 

Oct. 

1,309 

194 

0 

54,142 

2,380 

0 

1,309 

0 

139 

0 

Nov 

1,352 

0 

0 

52,694 

2,210 

0 

1,352 

0 

0 

0 

Dec. 
Total  or 
average 

15,965 

3,108 

0 

60,683 

0 

15,965 

16,978 

2,454 

0 

28—52411 


442 


WATER  RESOURCES  OF    CALIFORNIA. 

TABLE  16a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

USE  OF  RES 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 


Natural  flow  up  to  152  second- 

Flood  control  alone 

Flood  control  partially 

Water  drawn  f  ronr 

reservoir  only  as  required  by 

Constant  draft  o 

f  22  second- 

reservoir  operating  diagram 

only  as  required  by 

Flood 

Flood 

Run-off 

control 

control 

Year  and 
month 

at 

Azusa 

in 

acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 
passing 
Azusa 
during 
flood 
season 
at  rates 
less 
than  1,900 
second- 
feet  in 
acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 
spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

water 

passing 
Azusa 
during 
flood 
season 

at  rates 

less 

than  1,900 

second- 
feet  in 

acre-feet 

1921 

Jan. 

5,160 

71,728 

4,405 

19,991 

0 

0 

71,466 

4,405 

18,459 

Feb. 

4,490 

52,492 

4,490 

0 

0 

0 

52,410 

4,490 

0 

Ma-. 

15,400 

52,492 

7,288 

0 

0 

0 

51,188 

7,288 

0 

April 

6,070 

60,604 

6,070 

0 

214 

0 

57,948 

6,070 

0 

May 

15,700 

60,390 

6,835 

0 

295 

0 

56,433 

6,835 

0 

June 

8,i)80 

68,960 

7,920 

0 

379 

0 

63,664 

7,920 

0 

July 

3,830 

69,641 

3,830 

0 

450 

0 

63,054 

3,830 

0 

Aug. 

2,450 

69,191 

2,450 

0 

416 

0 

61,284 

2,450 

0 

Sept. 

1.840 

68,775 

1,840 

0 

323 

0 

59,549 

1,840 

0 

Oct. 

2,040 

68,452 

2,040 

0 

244 

0 

57,947 

2,040 

0 

Nov. 

1,800 

68,208 

1,800 

0 

163 

0 

56,375 

1,800 

0 

Dec. 

119,000 

68,045 

5,045 

42,364 

0 

0 

54,923 

5,045 

41,740 

Total  or 
average 

186,760 

54,013 

62,355 

2,484 

0 

54,013 

60,199 

1922 

Jan. 

62,100 

139,636 

9,344 

108,684 

0 

0 

125,786 

P.  344 

107,332 

Feb. 

88,900 

83,708 

8,440 

98.166 

0 

0 

69,858 

8,410 

83.316 

Mar. 

47,800 

66,002 

9,344 

3,576 

0 

0 

65,780 

9,344 

2,882 

April 

31,400 

100,882 

9,042 

0 

321 

0 

100,002 

9,042 

0 

May 

24,700 

122,919 

9,344 

0 

482 

0 

120,734 

9,344 

0 

June 

14,400 

137,793 

9,042 

0 

605 

0 

134,264 

9,042 

0 

July 

9,100 

142,546 

8,576 

0 

720 

0 

137,722 

8,576 

0 

Aug. 

5,080 

142,350 

5,080 

0 

670 

0 

136,194 

5,080 

0 

Sept. 

3,290 

141,080 

3,290 

0 

516 

0 

134,196 

3,290 

0 

Oct. 

3,110 

141,164 

3,110 

0 

393 

0 

132,391 

3,110 

0 

Nov. 

5,310 

140,771 

4,519 

37,066 

246 

0 

130,664 

4,519 

25.655 

Dec. 

21,500 

104,250 

8,456 

54.0i'3 

0 

0 

104.249 

8,456 

52,740 

Total  or 
average 

316,690 

87,587 

301,585 

3.953 

0 

87,587 

271,925 

1923 

Jan. 

7,130 

63,201 

6,968 

13,408 

0 

0 

63.201 

0,968 

12,056 

Feb. 

7,830 

49,955 

7,791 

0 

0 

0 

49,955 

7,791 

0 

Mar. 

7,.320 

49.994 

7,320 

0 

0 

0 

48,772 

7,320 

0 

April 

8,330 

49.994 

8,079 

0 

190 

0 

47,420 

8,079 

0 

May 

5,480 

50,055 

5,480 

0 

258 

0 

40,180 

5,480 

0 

June 

3,700 

49,797 

3,700 

0 

309 

0 

44,584 

3,700 

0 

July 

2,420 

49,488 

2,420 

0 

363 

0 

42,987 

2,420 

0 

Aug. 

1,990 

49,125 

1,990 

0 

337 

0 

41,304 

1,990 

0 

Sept. 

1,750 

48,788 

1,750 

0 

262 

0 

39,653 

1,750 

0 

Oct. 

1,710 

48,526 

1,710 

0 

198 

0 

38,112 

1,710 

0 

Nov. 

1,960 

48,328 

1,960 

0 

131 

0 

30,589 

1,960 

0 

Doc. 

2,130 

48,197 

2,130 

0 

0 

0 

35,169 

2,130 

0 

Total  or 
average 

51.750 

61,298 

13.408 

2,048 

0 

51,298 

12,056 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


443 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

THREE  STEPS  IN  COORDINATING  THE 

ERVOIR  SPACE. 

tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  16,  page  182.) 


Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 


feet  passed  for  prior  rights. 


444 


WATER  RESOURCES   OF   CALIFORNIA. 


TABLE  16a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

USE  OF  RES 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 


Natural  flow  up  to  152  second- 

Flood  control  alone 

Flood  control  partially 

Wat< 

r  drawn  from  reservoir  only  as  required  by 

Constant  draft  of  22  second- 

reservoir  operating  diagram 

only  as  required  by 

Flood 

Flood 

Run-off 

control 

control 

Year  and 

at 

water 

water 

month 

Azusa 

in 

acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

passing 
Azusa 
during 
flood 
season 
at  rates 
less 
than  1,900 
second- 
feet  in 
acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

passing 
Azusa 
during 
flood 
season 
at  rates 
less 
than  1,900 
second- 
feet  in 
acre-feet 

1924 

Jan. 

2,170 

48,197 

2,170 

0 

0 

0 

33,817 

2,170 

0 

Feb. 

1,790 

48,197 

1,790 

0 

0 

0 

32,465 

1,790 

0 

Mar. 

4,130 

48,197 

3,714 

0 

0 

0 

31,200 

3,714 

0 

April 

6,190 

48,613 

6,190 

0 

188 

0 

30,264 

6,190 

0 

May 

3,650 

48,425 

3,650 

0 

252 

0 

28,814 

3,050 

0 

June 

1,660 

48,173 

1,660 

0 

303 

0 

27.276 

1,660 

0 

July 

1,000 

47,870 

1,000 

0 

359 

0 

25.753 

1,000 

0 

Aug. 

756 

47,511 

756 

0 

329 

0 

24.153 

756 

0 

Sept. 

744 

47,182 

744 

0 

256 

0 

22,579 

744 

0 

Oct. 

873 

46,926 

873 

0 

196 

0 

21,103 

873 

0 

Nov. 

1,190 

46,730 

1,190 

0 

129 

0 

19,628 

1,190 

0 

Dec. 

1,780 

46,601 

1,780 

0 

0 

0 

18,240 

1,780 

0 

Total  or 

average 

25,933 

25,517 

0 

2,012 

0 

25,517 

0 

1925 

Jan. 

1.710 

46,601 

1,710 

0 

0 

0 

16,888 

1,710 

0 

Feb. 

1,620 

46,001 

1,620 

0 

0 

0 

15..536 

1,620 

0 

Mar. 

2,510 

46,601 

2,423 

0 

0 

0 

14,314 

2,423 

0 

April 

7,200 

46,688 

5,765 

0 

184 

0 

13,049 

5,765 

0 

May 

3,050 

47,939 

3,050 

0 

252 

0 

13,086 

3,(150 

0 

June 

1,840 

47,087 

1,840 

0 

295 

0 

11,629 

1,840 

0 

July 

824 

47,392 

824 

0 

349 

0 

10,189 

824 

0 

Aug. 

621 

47,043 

621 

0 

329 

0 

8,696 

621 

0 

Sept. 

492 

46,714 

492 

0 

254 

0 

7,227 

492 

0 

Oct. 

873 

46.460 

873 

0 

194 

0 

5,837 

873 

0 

Nov. 

1,010 

46,206 

1,010 

0 

127 

0 

4,433 

1,010 

0 

Dec. 

1,650 

46,139 

1,650 

0 

0 

0 

3,096 

1,650 

0 

Total  or 

nvcrage 

23,400 

21.878 

0 

1,984 

0 

21,878 

0 

1926 

Jan. 

1,540 

46,139 

1„540 

0 

0 

0 

1,744 

1,540 

0 

Feb. 

7,940 

46,139 

5,485 

0 

0 

0 

3»2 

5,485 

0 

Mar. 

3,650 

48,594 

3,650 

0 

0 

0 

1,625 

3,650 

0 

April 
May 

69,000 

48,594 

8,233 

0 

274 

0 

273 

8,233 

0 

13,000 

109,087 

9,142 

0 

434 

0 

59,572 

9,142 

0 

June 

5,500 

112.511 

5,500 

0 

520 

0 

61,785 

5,500 

0 

July 

3,120 

111,991 

3,120 

0 

611 

0 

60,127 

3,120 

0 

Aug. 

2,070 

111,380 

2.070 

0 

567 

0 

.58.367 

2,070 

0 

Sept. 

1,580 

110,813 

1,580 

0 

436 

0 

56,642 

1,580 

0 

Oct. 
Nov. 
Dec. 

110,377 

55,049 

Total  or 
average 

107.400 

40,320 

0 

2,842 

0 

40.320 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


445 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

THREE  STEPS  IN  COORDINATING  THE 

ERVOIR  SPACE. 

tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  16,  page  182.) 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet. 
feet  passed  for  prior  rights. 


446 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  16a  (Concluded).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

USE  OF  RES 
Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 


Height  of  dam  383  feet. 

Capacity  of  reservoir  180,000  acre-feet. 


Natural  flow  up  to  152  second- 


Run-off 

at 
Azusa 

in 
acre-feet 

Flood  control  alone 

Water  drawn  from  reservoir  only  as  required  by 
reservoir  operating  diagram 

Flood  control  partially 

Constant  draft  of  22  second- 
only  as  required  by 

Year  and 

month 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

Flood 
control 
water 
passing 
Azusa 
during 
flood 
season 
at  rates 
less 
than  1,900 
second- 
feet  in 
acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 

spillway 

in 
acre-feet 

Stage  of 
reserv-oir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

Flood 
control 
water 
passing 
Azusa 
during 
flood 
season 
at  rates 
less 
than  1,900 
second- 
feet  in 
acre-feet 

Total  for 
period, 
Jan. 1, 
1897.  to 
Ocf.1, 
1926 

Average 

for 

period, 

Jan.1, 

1897,  to 

Oct.  1, 

1926 

3.731,977 
125.445 

1.513,303 
50,867 

"2,076,091 
"69,785 

87,430 
2,939 

7,426 
250 

1,513,303 
50.867 

1,672,152 
1-56.207 

•  In  the  cumpjtitions  for  this  table  the  period  of  analysis  cbsed  with  47,727  acre-feet  more  water  in  storage  than  at  the 
beginning,  thecTiivalent  of  IGOl  v:ra-feef  per  season.  Since  in  the  computations  this  water  was  stored  in  the  last  year  of  the 
psriod  of  analysis,  the  exact  yield  of  flood  control  water  for  the  p3riod  is  greater  than  here  shown  by  this  amount. 


THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


447 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

THREE  STEPS  IN  COORDINATING  THE 

ERVOIR  SPACE. 

tions  Carried  Out  on  a  Daily  Basis. 

mary,  see  Table  16,  page  182.) 

Maximum  controlled  flow  at  Azusa  1,900  second-feet. 
Maximum  flood  control  reserve  131,000  acre-feet, 
feet  passed  for  prior  rights. 


coordinated  with  conservation 

feet  maintained,  other  drafts 
reservoir  operating  diagram 

Flood  control  completely  coordinated  with  conservation 

Reservoir  emptied  each  summer  to  a  level  that  would  maintain  constant 

draft  through  critical  period;  constant  draft  of  22  second-feet 

maintained,  other  drafts  only  as  required  by 

reser\-oir  operating  diagram 

Constant 

draft 

from 

over-year 

storage 

(22 
second- 
feet)  in 
acre-feet 

Evapora- 
tion from 
reservoir 
surface 

in 
acre-feet 

Waste 

over 
spillway 

in 
acre-feet 

Stage  of 
reservoir 

at 
beginning 

of 
month  in 
acre-feet 

Passed 
by  dam 
for  prior 
rights  in 
acre-feet 

Flood 
control 
water 
passing 
Azusa 
during 
flood 
season 
at  rates 
less 

than  1,900 
second- 
feet  in 

acre-feet 

Constant 

draft 

from 

over-year 

storage 

(22 
second- 
feet)  in 
acre-feet 

Variable 

summer 

draft 

from 

seasonally 

stored 

water  in 

acre-feet 

Evapora- 
tionfrom 
reservoir 
surface 

in 
acre-feet 

Waste 
over 

spillway 

in 
acre-feet 

Year  and 
month 

473,905 
15,930 

76,867 
2,584 

3,351 
113 

1,513,303 
50,867 

b1 ,01 0,662 
b33,972 

473,905 
15,930 

676,322 
22,734 

65,386 
2,198 

0 
0 

Total  for 
period, 
Jan.1, 
1897,  to 
Oct.  1, 
1926 

Average 

for 

period, 

Jan.1, 

1897,  to 

Oct.  1, 

1926 

*>  These  figures  contain  7601  acre-feet  total  or  an  average  of  256  acre-feet  per  season  of  water  contributed  from  outside 
the  e.xact  period,  of  analysis.  In  the  computations  from  which  this  table  is  prepared,  the  water  in  storage  on  October  1,  1926, 
the  end  of  the  period,  is  less  by  this  amount  than  on  .January  I,  1897,  the  beginning  of  the  period.  Since  in  the  computations 
this  water  was  released  as  flood  control  water  during  t  he  first  flood  season  of  the  period ,  the  exact  yield  of  flood  control  water 
for  the  period,  is  less  than  here  shown  by  this  amount. 


448 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  17a.     SAN  GABRIEL  RESER 

COMPARISON  OF  WATER  YIELD  FOR 

FOR  FLOOD  CONTROL  AND 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 
Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 


Height  of  dam.  383  feet.   Capacity  of  reservoir,  180,000  acre-feet 

Constant  draft  of  22  second-feet  maintained,  other  drafts  only 

Run-off  at 

as  required  by  reservoir  operating  diagi 

am 

Year  and 
month 

Flood  control 

Azusa  in 
acre-feet 

Stage  of 
reservoir  at 
beginning 
of  month  in 

acre-feet 

Passed  by 

dam  for 

prior  rights 

in  acre-feet 

water  passing 
Azusa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 

Constant  draft 
from  over-year 

storage 

(22  second-feet) 

in  acre-feet 

Evaporation 

from  reservoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

acre-feet 

1897 

Jan. 

3,617 

62,650 

3,617 

11.779 

1,352 

0 

0 

Feb. 

19,146 

49,519 

7,262 

4,628 

1,222 

0 

0 

Mar 

28,623 

55,553 

9.344 

0 

1,352 

0 

0 

April 

17,519 

73,480 

9,042 

0 

1,309 

235 

0 

May 

8,851 

80,413 

8,126 

0 

1.352 

353 

0 

June 

4,033 

79,433 

4,033 

0 

1,309 

412 

0 

July 

2,343 

77,712 

2,343 

0 

1,352 

485 

0 

Aug. 

1,613 

75,875 

1,013 

0 

1,352 

440 

0 

Sept. 

1,226 

74,083 

1,226 

0 

1,309 

337 

0 

Oct. 

5,564 

72,437 

2,622 

0 

1,352 

258 

0 

Nov. 

1,860 

73,769 

1,860 

0 

1,309 

171 

0 

Dec. 

1,875 

72,289 

1,875 

0 

1,352 

0 

0 

Total  or 
average 

96,270 

52,963 

16,407 

15,922 

2,691 

0 

1898 

Jan. 

2,453 

70,937 

2,453 

10.849 

1.352 

0 

0 

Feb. 

2,241 

58,736 

2,241 

0 

1,222 

0 

0 

Mar. 

2,131 

57,514 

2,131 

0 

1,352 

0 

0 

April 

1,950 

56,162 

1,950 

0 

1,309 

202 

0 

May 

2,213 

54,651 

2,213 

0 

1,352 

270 

0 

June 

1,1.59 

53,029 

1,159 

0 

1,309 

325 

0 

July 

672 

51,395 

672 

0 

1,352 

369 

0 

Aug. 

456 

49,674 

456 

0 

1,352 

337 

0 

Sept. 

467 

47,985 

467 

0 

1,309 

256 

0 

Oct. 

533 

46,420 

533 

0 

1,352 

192 

0 

Nov. 

580 

44,876 

580 

0 

1,309 

125 

0 

Dec. 

832 

43,442 

832 

0 

1,352 

0 

0 

Totiil  or 
average 

15,687 

15,687 

10,849 

15.922 

2.076 

0 

1899 

Jan. 

1,414 

42,090 

1,414 

0 

1,352 

0 

0 

Feb. 

1,244 

40,738 

1.244 

0 

1,222 

0 

0 

Mar. 

1,623 

,39,516 

1,623 

0 

1,352 

0 

0 

April 

1,262 

38,164 

1,262 

0 

1,309 

161 

0 

May 

842 

36,694 

842 

0 

1,352 

214 

0 

June 

565 

35,128 

565 

0 

1,309 

248 

0 

July 

221 

33,571 

221 

0 

1.352 

288 

0 

Aug. 

295 

31,931 

295 

0 

1.3.52 

260 

0 

Sept. 

220 

30,319 

220 

0 

1,309 

198 

0 

Oct. 

083 

28.812 

683 

0 

1,352 

147 

0 

Nov 

847 

27,313 

847 

0 

1.309 

91 

0 

Dec. 
Total  or 
avcriige 

1,247 

25,913 

1,247 

0 

1.352 

0 

0 

10,463 

10.463 

0 

15.922 

1.607 

0 

1900 

Jan. 

1.968 

24.561 

1.968 

0 

1.352 

0 

0 

Feb. 

1,111 

23.209 

1.111 

0 

1.222 

0 

0 

Mar. 

1.230 

21.987 

1.230 

0 

1.352 

0 

0 

April 

1,012 

20.635 

1,012 

0 

1.309 

115 

0 

May 

2,275 

19,211 

2,275 

0 

1,352 

147 

0 

June 

893 

17,712 

893 

0 

1,309 

180 

0 

July 

369 

10,223 

309 

0 

1,352 

192 

0 

Aug. 

246 

14,679 

246 

0 

1,352 

169 

0 

Sept. 

238 

13,1,58 

238 

0 

1,309 

121 

0 

Oct. 

307 

11,728 

307 

0 

1,352 

95 

0 

Nov. 

11,068 

10,281 

1,058 

0 

1.309 

59 

0 

Dec. 
Total  or 

1,269 

18,923 

1,260 

0 

1.352 

0 

0 

average 

21,986 

11,976 

0 

15.922 

1,078 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


449 


VOIR  ON  SAN  GABRIEL  RIVER. 

TWO  SIZES  OF  RESERVOIR  OPERATING 
CONSTANT  DRAFT  ONLY, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  17,  page  184.) 

Maximum  flood  control  reserve  131,000  acre-feet, 
feet  passed  for  prior  rights. 


Height  of  dam 

,  425  feet.    Capacity  of  reservoir,  240,000  acre-feet 

Constant  draft  of  41  second-feet  maintained,  ottier  drafts  only 

as 

equired  by  reservoir  operating  diagram 

Flood  control 

Year  and 

Stage  of 
reservoir  at 
beginniEg 
of  month  in 

acre-feet 

Passed  by 

dam  for 

prior  rights 

in  acre-feet 

water  passing 
Azusa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 
acre-feet 

Constant  draft 
from  over-year 

storage 

(41  second-feet) 

in  acre-feet 

Evaporation 

from  reservoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

month 

1897 

122,650 

3.617 

10,611 

2,520 

0 

0 

Jan. 

109,519 

7,262 

4,478 

2,276 

0 

0 

Feb. 

114,649 

9,344 

0 

2,520 

0 

0 

Mar. 

131,408 

9,042 

0 

2,439 

363 

0 

April 

137,083 

8,126 

0 

2,520 

494 

0 

May 

134,794 

4,033 

0 

2,439 

583 

0 

•June 

131,772 

2,343 

0 

2,520 

674 

0 

July 

128,578 

1,613 

0 

2.520 

621 

0 

Aug. 

125,437 

1,226 

0 

2,439 

472 

0 

Sept. 

122,526 

2,622 

0 

2,520 

357 

0 

Oct. 

122,591 

1,860 

0 

2,439 

238 

0 

Nov. 

119,914 

1,875 

0 

2,520 

0 

0 

Dec. 

Total  or 
average 

52,963 

15,089 

29,672 

3,802 

0 

1898 

117,394 

2,453 

0 

2,520 

0 

0 

Jan. 

114,874 

2,241 

0 

2,276 

0 

0 

Feb. 

112,598 

2,131 

0 

2,520 

0 

0 

Mar. 

110,078 

1.950 

0 

2,439 

313 

0 

April 

107,326 

2,213 

0 

2,520 

410 

0 

May 

104,396 

1,159 

0 

2,439 

490 

0 

June 

101,467 

672 

0 

2,520 

565 

0 

July 

98,382 

456 

0 

2,520 

516 

0 

Aug. 

95,346 

467 

0 

2,439 

391 

0 

Sept 

92,516 

533 

0 

2,520 

293 

0 

Oct. 

89,703 

580 

0 

2,439 

192 

0 

Nov. 

87,072 

832 

0 

2,520 

0 

0 

Dec. 
Total  or 

15,687 

0 

29,672 

3,170 

0 

average 
1899 

84,552 

1,414 

0 

2,520 

0 

0 

Jan. 

82,032 

1,244 

0 

2,276 

0 

0 

Feb. 

79,756 

1,623 

0 

2.520 

0 

0 

Mar. 

77,236 

1,262 

0 

2,439 

246 

0 

April 

74,551 

842 

0 

2,520 

325 

0 

May 

71,706 

565 

0 

2,439 

383 

0 

June 

68,884 

221 

0 

2,520 

440 

0 

July 

65,924 

295 

0 

2,520 

399 

0 

Aug. 

63,005 

220 

0 

2,439 

301 

0 

Sept. 

60,265 

683 

0 

2,520 

224 

0 

Oct. 

57,521 

847 

0 

2,439 

143 

0 

Nov. 

54,939 

1,247 

0 

2,520 

0 

0 

Dec. 
Total  n 
average 

10,463 

0 

29,672 

2,461 

0 

1900 

52,419 

1,968 

0 

2,520 

0 

0 

Jan. 

49,899 

1,111 

0 

2,276 

0 

0 

Feb. 

47,623 

1,230 

0 

2,520 

0 

0 

Mar. 

45,103 

1,012 

0 

2,439 

176 

0 

April 

42,488 

2,275 

0 

2.520 

230 

0 

May 

39,738 

893 

0 

2,439 

264 

0 

June 

37,035 

369 

0 

2,520 

299 

0 

July 

34,216 

246 

0 

2,520 

268 

0 

Aug. 

31,428 

238 

0 

2,439 

200 

0 

Sept. 

28,789 

307 

0 

2,520 

145 

0 

Oct. 

26,124 

1,058 

0 

2,439 

95 

0 

Nov. 

33,600 

1,269 

0 

2.520 

0 

0 

Dec. 
Total  or 
average 

11,976 

0 

29,672 

1,677 

0 

450 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  17a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

FOR  FLOOD  CONTROL  AND 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 
Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 


Height  of  dam,  383  feet.   Capacity  of  reservoir,  180,000  acre-feet 

Constant  draft  of  22  second-fee 

maintained,  other  drafts  only 

Run-off  at 

as  required  by  reservoir  operating  diagram 

Year  and 

month 

i  Flood  control 

Azusa  in 
acre-feet 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Passed  by 

dam  for 

prior  rights 

in  acre-feet 

water  passing 
Azusa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 

Constant  draft 
from  over-year 

storage 

(22  second-feet) 

in  acre-feet 

Evaporation 

from  reservoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

acre-feet 

1901 

Jan. 

10,391 

17,571 

6,661 

0 

1,352 

0 

0 

Feb. 

38.709 

19,949 

8,350 

0 

1,222 

0 

0 

Mar. 

13,589 

49,086 

9,138 

0 

1,352 

0 

0 

.\pril 

6,545 

52.185 

6,545 

0 

1,309 

192 

0 

May 

7,440 

50,684 

6,990 

0 

1,352 

260 

0 

June 

3,749 

49,522 

3,749 

0 

1,309 

305 

0 

July 

1.845 

47,908 

1,845 

0 

1,352 

353 

0 

Aug. 

1.240 

46,203 

1,240 

0 

1,352 

321 

0 

Sept- 

1,012 

44,530 

1,012 

0 

1,309 

246 

0 

Oct. 

1,476 

42,975 

1,476 

0 

1,352 

184 

0 

Nov. 

1,904 

41.439 

1,904 

0 

1,309 

115 

0 

Dec. 

1,660 

40,015 

1,660 

0 

1,352 

0 

0 

Total  or 
average 

89,560 

50,570 

0 

15,922 

1,976 

0 

1902 

Jan. 

1,722 

38,663 

1,722 

0 

1,352 

0 

0 

Feb. 

2,055 

37,311 

2,055 

0 

1,222 

0 

0 

Mar. 

6,088 

36,089 

5,590 

0 

1,352 

0 

0 

April 

3,928 

35,235 

3,928 

0 

1.309 

153 

0 

May 

2,398 

33,773 

2,398 

0 

1,352 

204 

0 

June 

1,190 

32,217 

1,190 

0 

1,309 

236 

0 

July 

676 

30,672 

676 

0 

1,352 

272 

0 

Aug. 

430 

29,048 

430 

0 

1,352 

246 

0 

Sept. 

298 

27,450 

298 

0 

1,309 

186 

0 

Oct. 

430 

25,955 

430 

0 

1,352 

139 

0 

Nov. 

1,131 

24,464 

1,131 

0 

1,309 

87 

0 

Dec. 

1,968 

23,068 

1,968 

0 

1,352 

0 

0 

Total  or 
average 

22,314 

21,816 

0 

15,922 

1.523 

0 

1903 

Jan. 

9,100 

21,716 

2.536 

0 

1,352 

0 

0 

Feh 

5,665 

26,928 

5,497 

0 

1,222 

0 

0 

Mar. 

15,802 

25.874 

7.898 

0 

1,352 

0 

0 

April 

47,127 

32,426 

9.042 

0 

1,309 

208 

0 

May 

13,343 

68,994 

9.116 

0 

1,352 

323 

0 

Jdne 

5,653 

71,546 

5.653 

0 

1,309 

385 

0 

July 

2,644 

69.852 

2,644 

0 

1,352 

446 

0 

Aug. 

1,783 

68,054 

1,783 

0 

1.352 

410 

0 

Sept. 

1,488 

66,292 

1,488 

0 

1.309 

313 

0 

Oct. 

1.476 

64,670 

1,476 

0 

1,352 

236 

0 

Nov. 

1,428 

63,082 

1,428 

0 

1,309 

155 

0 

Dec. 

1,476 

61.618 

1,476 

0 

1,352 

0 

0 

Total  or 
average 

106.085 

50.037 

0 

15,922 

2.476 

0 

1904 

Jan. 

1,500 

60.266 

1,500 

0 

1,352 

0 

0 

Feb. 

2,744 

58,914 

2,177 

0 

1,265 

0 

0 

Mar. 

6,813 

58,216 

4.724 

0 

1.352 

0 

0 

April 
May 

5,337 

58,953 

5,337 

0 

1,309 

208 

0 

4,089 

57,436 

4.089 

0 

1,352 

280 

0 

June 

1.517 

55,801 

1.517 

0 

1,309 

329 

0 

July 

861 

54,166 

861 

0 

1,352 

383 

0 

Aug. 

793 

52.431 

793 

0 

1,352 

349 

0 

Sept. 

643 

50,730 

643 

0 

1,309 

266 

0 

Oct. 

738 

49,155 

738 

0 

1,352 

206 

0 

Nov. 

762 

47,597 

762 

0 

1,309 

133 

0 

Dec. 

1.039 

46.155 

1,039 

0 

1,.352 

0 

0 

Total  or 
average 

26,836 

24,180 

0 

15,965 

2,154 

0 

THE    CONTROL   OF   FLOODS   BY   RESERVOIRS. 


451 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  SIZES  OF  RESERVOIR  OPERATING 
CONSTANT  DRAFT  ONLY, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  17,  page  184.) 

Maximum  flood  control  reserve  131,000  acre-feet, 
feet  passed  for  prior  rights. 


Height  of  dam 

425  feet.    Capacity  of  reservoir,  240,000  acre-feet 

Constant  draft  of  41  second-feet  maintained,  other 

drafts  only 

as  required  by  reservoir  operating  diagra 

m 

Flood  control 

Year  and 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Passed  by 

dam  for 

prior  rights 

in  acre-feet 

water  passing 
Azusa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 
acre-feet 

Constant  draft 
from  over-year 

storage 

(41  second-feet) 

in  acre-feet 

Evaporation 

from  reservoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

month 

1901 

31,080 

6,661 

0 

2,.520 

0 

0 

Jan. 

32,290 

8,350 

0 

2,276 

0 

0 

Feb. 

60,373 

9,138 

0 

2,520 

0 

0 

Mar. 

62,304 

6,545 

0 

2,439 

214 

0 

April 

59,651 

6,990 

0 

2,520 

284 

0 

May 

57,297 

3,749 

0 

2,439 

331 

0 

June 

54,527 

1,845 

0 

2,520 

381 

0 

July 

51,626 

1,240 

0 

2,520 

341 

0 

Aug. 

48,765 

1,012 

0 

2,439 

256 

0 

Sept. 

46,070 

1,476 

0 

2,520 

188 

0 

Oct. 

43,362 

1,904 

0 

2,439 

121 

0 

Nov. 

40,802 

1,660 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

50,570 

0 

29,672 

2,116 

0 

1902 

38,282 

1,722 

0 

2,520 

0 

0 

Jan. 

35,762 

2,055 

0 

2,276 

0 

0 

Feb. 

33,486 

5,590 

0 

2,520 

0 

0 

Mar. 

31,464 

3,928 

0 

2,439 

143 

0 

April 

28,882 

2,398 

0 

2,520 

182 

0 

May 

26,180 

1,190 

0 

2,439 

208 

0 

June 

23,533 

676 

0 

2,520 

232 

0 

July 

20,781 

430 

0 

2,520 

202 

0 

Aug 

18.059 

298 

0 

2,439 

145 

0 

Sept. 

15.475 

430 

0 

2,520 

99 

0 

Oct. 

12,856 

1,131 

0 

2.439 

58 

0 

Nov.- 

10,359 

1,968 

0 

2,520 

0 

0 

Dec. 
Total  or 

21,816 

0 

29,672 

1,269 

0 

average 
1903 

7.839 

2,536 

0 

2,520 

0 

0 

Jan. 

11,883 

5,467 

0 

2,276 

0 

0 

Feb. 

9,775 

7,858 

0 

2,520 

0 

0 

Mar. 

15,159 

9,042 

0 

2,439 

171 

0 

April 

50,634 

9,116 

0 

2,520 

268 

0 

May 

52,073 

5,653 

0 

2,439 

311 

0 

June 

49,323 

2,644 

0 

2,520 

359 

0 

July 

46.444 

1,783 

0 

2,520 

321 

0 

Aug. 

43,603 

1,488 

0 

2,439 

240 

0 

Sept. 

40,924 

1,476 

0 

2,520 

176 

0 

Oct. 

38,228 

1,42» 

0 

2,439 

113 

0 

Nov. 

35,676 

1,476 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

50,037 

0 

29,672 

1.959 

0 

1904 

33,156 

1,500 

0 

2,520 

0 

0 

Jan. 

30,636 

2,177 

0 

2,358 

0 

0 

Feb. 

28,845 

4,724 

0 

2,520 

0 

0 

Mar. 

28,414 

5,337 

0 

2,439 

135 

0 

April 

25,840 

4,089 

0 

2,520 

173 

0 

May 

23.147 

1,517 

0 

2,439 

194 

0 

June 

20,514 

861 

0 

2,520 

216 

0 

July 

17,778 

793 

0 

2,520 

184 

0 

Aug. 

15,074 

643 

0 

2.439 

129 

0 

Sept. 

12,506 

738 

0 

2,520 

87 

0 

Oct. 

9,899 

762 

0 

2,439 

50 

0 

Nov. 

7,410 

1,039 

0 

2,520 

0 

0 

Dec. 
Total  or 

24,180 

0  1                  29,754 

j                    1,168 

1                       0 

average 

452 


WATER   RESOURCES  OF    CALIFORNIA. 


TABLE  17a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

FOR  FLOOD  CONTROL  AND 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 
Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 


Height  of  dam,  383  feet.   Capacity  of  reservoir,  180,000  acre-feet 

Constant  draft 

0 f  22  second-feet  maintained,  other  drafts  only 

Run-ofF  at 
Azusa  in 
acre-feet 

as  required  by  reservoir  operating  diagram 

Year  and 
month 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Passed  oy 

dam  for 

prior  rights 

in  acre-feet 

Flood  control 
water  passing 
Azusa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 

Constant  draft 
from  over-year 

storage 

(22  second-feet) 

in  acre-feet 

Evaporatioa 

from  reservoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

acre-feet 

1905 

Jan. 

2,251 

44,803 

2,251 

0 

1,352 

0 

0 

Feb. 

25,S80 

43,451 

8,206 

6,204 

1,222 

0 

0 

Mar. 

75,140 

53,699 

9,281 

16,231 

1,352 

0 

0 

April 

19,580 

101,975 

9,042 

0 

1,309 

311 

0 

May 

17.090 

1 10,893 

9,344 

0 

1,352 

438 

0 

June 

8,271 

116,849 

7,960 

0 

1,309 

529 

0 

July 

5,103 

115,322 

5,103 

0 

1,352 

621 

0 

Aug. 

2,631 

113,349 

2,631 

0 

1,352 

571 

0 

Sept. 

1,869 

111,426 

1,869 

0 

1.309 

436 

0 

Oct. 

1.770 

109,681 

1,770 

0 

1.352 

329 

0 

Nov. 

2,660 

108,000 

2,660 

3,610 

1,309 

220 

0 

Dec. 

2,470 

102,861 

2,470 

6,944 

1,352 

0 

0 

Total  or 

average 

164,715 

62,587 

32,989 

15,922 

3,455 

0 

1906 

Jan. 

4,240 

94,565 

3,033 

33,008 

1.352 

0 

0 

Feb. 

3,960 

60,212 

3,960 

0 

1,222 

0 

0 

Mar. 

129,000 

58,990 

7,561 

30,250 

1,352 

0 

0 

April 

34,600 

148,827 

9,042 

20,735 

1,309 

381 

0 

May 

21,000 

151,960 

9,344 

0 

1,352 

541 

0 

June 

15,500 

161,723 

9,042 

0 

1,309 

674 

0 

July 

9,350 

166,198 

8,664 

0 

1,352 

803 

0 

Aug. 

4,490 

164,729 

4,490 

0 

1,352 

738 

0 

Sept. 

2.840 

162,639 

2,840 

0 

1,309 

567 

0 

Oct. 

2,450 

160,763 

2,450 

0 

1.352 

430 

0 

•  Nov. 

2,400 

158,981 

2,400 

5.941 

1,309 

286 

0 

Dec. 
Total  or 
average 

11,600 

151,445 

4,030 

94,462 

1,352 

0 

0 

241,430 

67.456 

184.996 

15,922 

4,420 

0 

1907 

Jan. 

58,400 

63,201 

9,217 

56,159 

1.352 

0 

0 

Feb. 

47,100 

54,873 

8.439 

29,904 

1,222 

0 

0 

Mar. 

116,000 

62,408 

9,344 

45,814 

1.352 

0 

0 

April 
May 

58,400 

121,898 

9,042 

453 

1.309 

391 

0 

21,500 

169,103 

9,344 

0 

1.352 

585 

0 

June 

15,100 

179,322 

9.042 

0 

1,309 

720 

3,351 

July 

8,360 

180,000 

7,920 

0 

1,352 

847 

0 

Aug. 

5,.390 

178.241 

5,390 

0 

1,3.52 

781 

0 

Sept. 

3,580 

176,108 

3,580 

0 

1,309 

599 

0 

Oct. 

4,090 

174,200 

4,090 

3,106 

1,352 

450 

0 

Nov. 

3,800 

169,292 

3.800 

53,565 

•1,309 

254 

0 

Dec. 

3.600 

114,164 

3,600 

12,164 

1,352 

0 

0 

Total  or 
average 

345,320 

82.808 

201.165 

15,922 

4,627 

3.351 

1908 

Jan. 

11.100 

100,648 

4,973 

24.273 

1.352 

0 

0 

Vvh. 

15,000 

81,150 

8,741 

35,256 

1.265 

0 

0 

Mar. 

12,700 

.50,888 

9,255 

0 

1,352 

0 

0 

April 

9,280 

.W.981 

8,056 

0 

l,30y 

196 

0 

May 

7.  IPO 

52.100 

7.139 

0 

1,.'<52 

262 

0 

June 

4.190 

50.537 

4,190 

0 

l.SO'.l 

309 

0 

July 

2,560 

48,'tl9 

2,,')60 

0 

1,352 

359 

0 

Aug. 

2,210 

47,208 

2.210 

0 

1.3.52 

325 

0 

Sept. 

1.820 

4.5,531 

1.820 

0 

1,309 

252 

0 

Oof. 

•  2,070 

43,970 

2,070 

0 

1,352 

186 

0 

Nov. 

1,<160 

42.432 

1,960 

0 

1.309 

123 

0 

Dec. 
Total  or 
avcriiKfi 

2,870 

41.000 

2,870 

0 

1,352 

0 

0 

72,950 

56,444 

59,529 

15,965 

2,012 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


453 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  SIZES  OF  RESERVOIR  OPERATING 
CONSTANT  DRAFT  ONLY, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  17,  page  184.) 

Maximum  flood  control  reserve  131,000  acre-feet, 
feet  passed  for  prior  rights. 


Height  of  dam,  425  feet.    Capacity  of  reservoir,  240,000  acre-feet 

Constant  draft  of  41  second-feet  maintained,  other  drafts  only 

as 

required  by  reservoir  operating  diagram 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Passed  by 

dam  for 

prior  rights 

in  acre-feet 

Flood  control 
water  passing 
Azusa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 
acre-feet 

Constant  draft 
from  over-year 

storage 

(41  second-feet) 

in  acre-feet 

Evaporation 

from  reservoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

Year  and 
month 

1905 

4,890 

2,251 

0 

2,520 

0 

0 

Jan. 

2,370 

8,206 

0 

2,276 

0 

0 

Feb. 

17,768 

9,281 

0 

2  520 

0 

0 

Mar. 

81,107 

9,042 

0 

2.439 

268 

0 

April 

88,938 

9,344 

0 

2,520 

377 

0 

May 

93,787 

7,960 

0 

2,439 

464 

0 

June 

91,195 

5,103 

0 

2,520 

527 

0 

July 

88,148 

2,631 

0 

2.520 

482 

0 

Aug. 

85,146 

1,869 

0 

2,439 

365 

0 

Sept. 

82,342 

1,770 

0 

2,520 

272 

0 

Oct. 

79,550 

2,660 

0 

2,439 

176 

0 

Nov. 

76.935 

2,470 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

62,587 

0 

29,672 

2,931 

0 

1906 

74,415 

3,633 

0 

2,520 

0 

0 

Jan. 

72,502 

3,960 

0 

2,276 

0 

0 

Feb. 

70,226 

7,561 

9,428 

2,520 

0 

0 

Mar. 

179,717 

9,042 

0 

2,439 

468 

0 

April 

202,368 

9,344 

0 

2,520 

658 

0 

May 

210,846 

9,042 

0 

2,439 

815 

0 

June 

214,050 

8.664 

0 

2,520 

960 

0 

July 

211,256 

4,490 

0 

2,520 

882 

0 

Aug. 

207,854 

2,840 

0 

2,439 

672 

0 

Sept. 

204,743 

2,450 

0 

2.520 

510 

0 

Oct. 

201,713 

2,400 

0 

2,439 

335 

0 

Nov. 

198,939 

4,030 

80,788 

2,520 

0 

0 

Dec. 
Total  or 
average 

67,456 

90,216 

29,672 

5,300 

0 

1907 

123,201 

9,217 

54,991 

2,520 

0 

0 

Jan 

114.873 

8,439 

28,878 

2,276 

0 

0 

Feb. 

122,380 

9,344 

44,618 

2,520 

0 

0 

Mar. 

181,898 

9,042 

360 

2,439 

496 

0 

April 

227,961 

9,344 

0 

2,520 

724 

0 

May 

236,873 

9,042 

0 

2,439 

886 

0 

June 

239,606 

7,920 

0 

2,520 

1,047 

0 

July 

236,479 

5,390 

0 

2,520 

958 

0 

.\ug. 

233,001 

3.580 

0 

2,439 

736 

0 

Sept 

229,826 

4,090 

0 

2,520 

557 

0 

Oct. 

226,749 

3,800 

49.817 

2,439 

329 

0 

Nov. 

174,164 

3,600 

11,787 

2,520 

0 

0 

Dec. 
Total  or 
average 

82,808 

190,451 

29.672 

5,733 

0 

1908 

159,857 

•1,973 

24,010 

2,520 

0 

0 

Jan. 

139,454 

8,741 

33,168 

2,358 

0 

0 

Feb. 

110,187 

9,255 

0 

2,520 

0 

0 

Mar. 

111,112 

8,656 

0 

2,439 

3)7 

0 

April 

108.980 

7,139 

0 

2,520 

420 

0 

May 

106,091 

4,190 

0 

2,439 

494 

0 

June 

103,158 

2,560 

0 

2,520 

573 

0 

July 

100,065 

2,210 

0 

2,520 

524 

0 

Aug. 

97,021 

1,820 

0 

2,439 

397 

0 

Sept. 

94,185 

2,070 

0 

2,520 

297 

0 

Oct. 

91,368 

1,960 

0 

2,439 

194 

0 

Nov. 

88,735 

2,870 

0 

2,520 

0 

0 

Dec. 

Total  or 
average 

56,444 

57,178 

29,754 

3,216 

0 

454 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  17a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

FOR  FLOOD  CONTROL  AND 

Monthly  Summary  of  Computa 

(F'or  corresponding  yearly  sum 
Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 


Height  of  dam,  383  feet.   Capacity  of  reservoir,  180,000  acre-feel 

Constant  draft 

of  22  second-feet 

maintained,  other  drafts  only 

Run-off  at 
Azusa  in 
acre-feet 

as  required  by  reservoir  operating  diagram 

Year  and 
month 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Passed  by 

dam  for 

prior  rights 

in  acre-feet 

Flood  control 
water  passing 
Azusa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 

Constant  draft 
from  over-year 

storage 

(22  second-feet) 

in  acre-feet 

Evaporation 

from  reservoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

acre-feet 

1909 

Jan. 

25,500 

39,648 

5,596 

8,681 

1,352 

0 

0 

Feb. 

59,400 

49,519 

8,440 

41,897 

1,222 

0 

0 

Mar. 

26,300 

57,360 

9,344 

0 

1,352 

0 

0 

April 

28,000 

72,964 

9,042 

0 

1,309 

262 

0 

May 

15,200 

90,351 

9,344 

0 

1,352 

381 

0 

June 

8,570 

94,474 

8,319 

0 

1,309 

460 

0 

July 

5,040 

92,956 

5,040 

0 

1,352 

537 

0 

Aug. 

3.120 

91,067 

3,120 

0 

1,352 

494 

0 

Sept. 

2,320 

89,221 

2,320 

0 

1,309 

377 

0 

Oct. 

2,310 

87,535 

2,310 

0 

1,352 

286 

0 

Nov. 

2,880 

85,897 

2,880 

0 

1,309 

188 

0 

Dec. 

20,900 

84,400 

6,346 

24,763 

1,352 

0 

0 

Total  or 
:iveraj?e 

199,540 

72,101 

75,341 

15,922 

2,985 

0 

910 

Jan. 

69,500 

72,839 

9,344 

81,516 

1,-352 

0 

0 

Feb. 

11,500 

50,127 

8,435 

2,292 

1,222 

0 

0 

Mar. 

9,590 

49,678 

9,029 

0 

1,352 

0 

0 

April 

8,270 

48,887 

8,120 

0 

1,309 

186 

0 

May 

5,050 

47,542 

5,050 

0 

1,352 

250 

0 

June 

3,500 

45,940 

3,560 

0 

1,309 

291 

0 

July 

2,450 

44,340 

2,450 

0 

1,352 

337 

0 

Aug. 

1,710 

42,651 

1,710 

0 

1,352 

307 

0 

Sept. 

1,370 

40,992 

1,370 

0 

1,309 

234 

0 

Oct. 

1,560 

39,449 

1,560 

0 

1,352 

174 

0 

Nov. 

1,870 

37,923 

1,870 

0 

1,309 

113 

0 

Dec. 

2,020 

36,501 

2,020 

0 

1,352 

0 

0 

Total  or 
average 

118,450 

54,518 

83,808 

15,922 

1,892 

0 

1911 

Jan. 

37,200 

35,149 

6,441 

6,949 

1,352 

0 

0 

Feb. 

44,300 

57,607 

8,440 

38,010 

1,222 

0 

0 

Mar. 

122,000 

54,235 

9,344 

55,857 

1,352 

0 

0 

Anri! 

28,200 

109,682 

9,042 

0 

1,309 

335 

0 

May 

16,600 

127,196 

9,344 

0 

1,352 

478 

0 

June 

7,500 

132,622 

7,322 

0 

1,309 

579 

0 

July 

5,230 

130,912 

5,230 

0 

1,352 

676 

0 

Aug. 

.3,610 

128,884 

3,610 

0 

1,352 

623 

0 

Sept 

2,830 

120,909 

2,830 

0 

1,309 

476 

0 

Oct. 

3,140 

125,124 

3,140 

0 

1,352 

361 

0 

Nov. 

2,800 

123,411 

2,800 

1,061 

1,309 

238 

0 

Dec. 

2,870 

120,803 

2,870 

22,352 

1,352 

0 

0 

Total  or 
average 

276.280 

70.413 

124,229 

15,922 

3,766 

0 

1912 

Jan. 

2,710 

97,099 

2,710 

0 

1,352 

0 

0 

Feb. 

2,2.30 

95,747 

2,230 

0 

1,205 

0 

0 

Mar. 

22,900 

94,482 

8,199 

490 

1,352 

0 

0 

April 

18,000 

107,335 

8,515 

0 

1,309 

315 

0 

May 

10,900 

115,196 

8.828 

0 

1,352 

442 

0 

June 

4,990 

115,474 

4,990 

0 

1,309 

625 

0 

July 

3.060 

113,640 

3,0f.0 

0 

1,352 

613 

0 

Aug. 

1.960 

111,675 

1,960 

0 

1,.352 

565 

0 

Sept. 

1.550 

109,758 

1,.5.50 

0 

1,309 

430 

0 

Oct. 

1,830 

108,019 

1,830 

0 

1,352 

327 

0 

Nov. 

1,730 

106,340 

1,730 

0 

1,309 

216 

0 

Dec. 

1,700 

104,815 

1,760 

0 

1,352 

0 

0 

Total  or 
average 

73,620 

47,362 

496 

15,965 

3,433 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


455 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  SIZES  OF  RESERVOIR  OPERATING 
CONSTANT  DRAFT  ONLY, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  17,  page  184.) 

Maximum  flood  control  reserve  131,000  acre-feet, 
feet  passed  for  prior  rights. 


Height  of  dam 

425  feet.    Capacity  of  reservoir,  240,000  acre-feet 

Constant  draft  of  41  second-feet  maintained,  other  drafts  only 

as  required  by  reservoir  operating  diagra 

m 

Flood  control 

Year  and 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Passed  by 

dam  for 

prior  rights 

in  acre-feet 

water  passing 
Azusa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 
acre-feet 

Constant  draft 
from  over-year 

storage 

(41  second-feet) 

in  acre-feet 

Evaporation 

from  reservoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

month 

1909 

86,215 

5,596 

0 

2,520 

0 

0 

Jan. 

103,599 

8,440 

35,296 

2,276 

0 

0 

Feb. 

116,987 

9,344 

0 

2,520 

0 

0 

Mar. 

131,423 

9,042 

0 

2,439 

375 

0 

April 

147,567 

9,344 

0 

2,520 

525 

0 

May 

150,378 

8,319 

0 

2,439 

631 

0 

June 

147,559 

5,040 

0 

2,520 

734 

0 

July 

144,305 

3,120 

0 

2,520 

672 

0 

Aug. 

141,113 

2,320 

0 

2,439 

512 

0 

Sept. 

138,162 

2,310 

0 

2,520 

385 

0 

Oct. 

135,257 

2,880 

0 

2,439 

254 

0 

Nov. 

132,564 

6,346 

11,759 

2,520 

0 

0 

Dec. 
Total  or 

72,101 

47,055 

29,672 

4,088 

average 
1910 

132,839 

9,344 

80,362 

2,520 

0 

0 

Jan. 

110,113 

8,435 

1,945 

2,276 

0 

0 

Feb. 

108,957 

9,029 

0 

2,520 

0 

0 

Mar. 

106,998 

8,120 

0 

2,439 

307 

0 

April 

104,402 

5,050 

0 

2,520 

407 

0 

May 

101,475 

3,560 

0 

2,439 

478 

0 

Jane 

98,558 

2,450 

0 

2,520 

555 

0 

July 

95,483 

1,710 

0 

2,520 

506 

0 

Aug. 

92,457 

1,370 

0 

2,439 

385 

0 

Sept. 

89,633 

1,560 

0 

2,520 

288 

0 

Oct. 

86,825 

1,870 

0 

2,439 

188 

0 

Nov. 

84,198 

2,020 

0 

2,520 

0 

0 

Dec. 
Total  or 

54,518 

82,307 

29,672 

3,114 

0 

average 
1911 

81,078 

6,441 

0 

2,520 

0 

0 

Jan. 

109,917 

8,440 

29,679 

2,276 

0 

0 

Feb. 

113,822 

9,344 

55,275 

2,520 

0 

0 

Mar. 

168,683 

9,042 

0 

2,439 

438 

0 

April 

184,964 

9,344 

0 

2,520 

617 

0 

May 

189,083 

7,322 

0 

2,439 

740 

0 

June 

186,082 

5,230 

0 

2,520 

865 

0 

July 

182,697 

3,010 

0 

2,520 

793 

0 

Aug. 

179,384 

2,830 

0 

2,439 

607 

0 

Sept. 

176,338 

3,140 

0 

2,520 

458 

0 

Oct. 

173,360 

2,800 

0 

2,439 

301 

0 

Nov. 

170,620 

2,870 

11,071 

2,520 

0 

0 

Dec. 

Total  or 
average 

70,413 

96,025 

29,672 

4,819 

0 

1912 

157,029 

2,710 

0 

2,520 

0 

0 

Jan. 

154,509 

2,230 

0 

2,358 

0 

0 

Fob. 

152,151 

8,199 

0 

2,520 

0 

0 

Mar. 

164,332 

8,515 

0 

2,439 

420 

0 

April 

170,958 

8,828 

0 

2,520 

575 

0 

May 

169,935 

4,990 

0 

2,439 

686 

0 

June 

166,810 

3,060 

0 

2,520 

799 

0 

July 

163,491 

1,900 

0 

2,520 

731 

0 

Aug. 

160,237 

1,550 

0 

2,439 

557 

0 

Sept. 

157,241 

1,830 

0 

2,520 

420 

0 

Oct. 

154,301 

1,730 

0 

2,439 

280 

0 

Nov. 

151,582 

1,760 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

47,362 

0 

29,754 

4,471 

0 

456 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  17a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

FOR  FLOOD  CONTROL  AND 

Monthly  Summary  of  Compute 

(For    orre  ponding  yearly  sum 
Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 


Heiflht  of  dam,  383  feet.    Capacity  of  resarvoir,  180,000  acre-feet 

Constant  draft 

of  22  second-feet 

maintained,  other  drafts  only 

Rim-off  at 

as  required  by  reservoir  operating  diagram 

Year  and 
month 

Flood  control 

Azusa  in 
acre-feet 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Passed  by 

dam  for 

priorrights 

in  acre-feet 

water  passing 
Aziisa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 

Constant  draft 
from  over-year 

storage 

(22  second-feet) 

in  acre-feet 

Evaporation 

from  reservoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

acre-feet 

1913 

Jan. 

2,910 

103,463 

2,910 

4.136 

1.352 

0 

0 

Feb. 

13,200 

97,975 

4.753 

24.767 

1,222 

0 

0 

Mar. 

10,200 

80,433 

8.759 

10,660 

1,352 

0 

0 

April 

7,140 

69,862 

7.091 

0 

1,309 

232 

0 

May 

4,970 

68,370 

4,970 

0 

1,352 

309 

0 

June 

2,890 

66,709 

2,890 

0 

1,309 

367 

0 

July 

1,690 

65,033 

1,690 

0 

1,352 

426 

0 

Aug. 

1,070 

63.255 

1,070 

0 

1,352 

391 

0 

Sept. 

893 

61.512 

893 

0 

1,309 

297 

0 

Oct. 

910 

59.906 

910 

0 

1,352 

224 

0 

Nov. 

2,280 

58,330 

2,280 

0 

1,309 

147 

0 

Dec. 

2,170 

56,874 

2,170 

0 

1,352 

0 

0 

Total  or 
average 

50,323 

40,386 

39,503 

15,922 

2.393 

0 

1914 

.Ian. 

61,400 

55,522 

6,271 

47,159 

1,352 

0 

0 

Feb. 

121,000 

62,140 

8,440 

58,284 

1,222 

0 

0 

Mar. 

48,000 

115,194 

9,344 

52,388 

1,352 

0 

0 

April 

21,400 

100,110 

9,042 

0 

1,309 

305 

0 

May 

16,900 

110,854 

9,344 

0 

1,352 

428 

0 

June 

9,580 

116,630 

8,585 

0 

1,309 

530 

0 

July 

5,570 

115,786 

5,570 

0 

1,352 

631 

0 

Aug. 

3,630 

113,803 

3,630 

0 

1,352 

572 

0 

Sept. 

2,730 

111,879 

2,730 

0 

1,309 

436 

0 

Oct. 

2,770 

110.134 

2,770 

0 

1,352 

331 

0 

Nov. 

2,440 

108.451 

2,440 

0 

1,309 

220 

0 

Dec. 

4,290 

106,922 

4,290 

40.981 

1,362 

0 

0 

Total  or 
average 

299,710 

72,456 

198,812 

15,922 

3,453 

0 

1915 

Jan. 

7,380 

64,589 

4.428 

8,659 

1,352 

0 

0 

Feb. 

30,200 

67.530 

8,412 

20,577 

1.222 

0 

0 

Mar. 

21,500 

57.519 

9.344 

0 

1,352 

0 

0 

April 

17,300 

68.323 

9,042 

0 

1,309 

238 

0 

May 

20.400 

75.034 

9,344 

0 

1,352 

343 

0 

June 

11,400 

84.395 

8,967 

0 

1,309 

434 

0 

July 

7,010 

85.085 

7,010 

0 

1,352 

508 

0 

Aug. 

3,980 

83.225 

3.980 

0 

1,352 

464 

0 

Sept. 

3,270 

81,409 

3,270 

0 

1,309 

365 

0 

Oct. 

2,770 

79.745 

2.770 

0 

1,352 

268 

0 

Nov. 

3.010 

78.125 

3.010 

0 

1,309 

176 

0 

Dec. 

3.580 

76.640 

3.580 

0 

1.352 

0 

0 

Total  or 
average 

131,800 

73,157 

29.230 

15.922 

2,786 

0 

1916 

Jan. 

148.000 

75,288 

8.759 

70,558 

1,352 

0 

0 

Feb. 

39,400 

142,619 

8.541 

100,407 

1,265 

0 

0 

Mar. 

34.800 

71,606 

9.344 

4,679 

1,352 

0 

0 

April 
May 

19.900 

91.031 

9.042 

0 

1,309 

288 

0 

10.400 

100.292 

9,130 

0 

1,352 

399 

0 

June 

5.830 

99.811 

5,830 

0 

1.309 

476 

0 

July 

4.770 

98.026 

4,770 

0 

1.352 

555 

0 

Aug. 

3,570 

96,119 

3,670 

0 

1.352 

612 

0 

Sept. 

2,810 

94.255 

2,810 

0 

1.309 

391 

0 

Oct. 

7,010 

92.555 

6.473 

0 

1.352 

295 

0 

Nov. 

4,130 

91.445 

4.130 

0 

1.309 

196 

0 

Dec. 

Tntftl  nr 

13,000 

89.940 

5.253 

33.734 

1.352 

0 

0 

1  utai  ur 

average 

294,220 

77.852 

209.378 

16.965 

3.112 

0 

THE   CONTROL   OF   FLOODS   BY   RESERVOIRS. 


457 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  SIZES  OF  RESERVOIR  OPERATING 
CONSTANT  DRAFT  ONLY, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  17,  page  184.) 

Maximum  flood  control  reserve  131,000  acre-feet, 
feet  passed  for  prior  rights. 


Height  of  dam,  425  feet.    Capacity  of  reservoir,  240,000  acre-feet 

Constant  draft  of  41  second-feet  maintained,  otiier  drafts  only 

as 

required  by  reservoir  operating  diagram 

Flood  control 

Year  and 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Passed  by 
dam  for 

water  passing 
Azusa  during 
flood  season  at 

Constant  draft 
from  over-year 

Evaporation 
from  reservoir 

Waste  over 

spillway 
in  acre-feet 

month 

prior  rights 
in  acre-feet 

rates  less  than 
1,900  second- 
feet  in 

storage 

(41  second-feet) 

in  acre-feet 

surface 
in  acre-feet 

acre-feet 

1913 

149,062 

2.910 

0 

2,520 

0 

0 

Jan. 

146,542 

4,753 

16,941 

2,276 

0 

0 

Feb. 

135,772 

8,759 

7,782 

2,520 

0 

0 

Mar. 

126,911 

7,091 

0 

2,439 

345 

0 

April 

124,176 

4,970 

0 

2,520 

460 

0 

May 

121,196 

2,890 

0 

2,439 

541 

0 

June 

118,216 

1,690 

0 

2,.520 

629 

0 

July 

115,067 

1,070 

0 

2,520 

675 

0 

Aug. 

111,972 

893 

0 

2,439 

436 

0 

Sept. 

109,097 

910 

0 

2,520 

327 

0 

Oct. 

106,250 

2,280 

0 

2,439 

216 

0 

Nov. 

103,595 

2,170 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

40,386 

24,723 

29,672 

3,529 

0 

1914 

101,075 

6,271 

31,544 

2,520 

0 

0 

Jan. 

122,140 

8,440 

57,228 

2,276 

0 

0 

Feb. 

175,196 

9,344 

51,782 

2,520 

0 

0 

Mar. 

159,550 

9,042 

0 

2,439 

424 

0 

April 

169,045 

9,344 

0 

2,520 

579 

0 

May 

173,502 

8,585 

0 

2,439 

696 

0 

June 

171,362 

5,570 

0 

2,520 

815 

0 

July 

168,027 

3,630 

0 

2,520 

746 

0 

Aug. 

164,761 

2,730 

0 

2,439 

569 

0 

Sept. 

161,753 

2,770 

0 

2,520 

430 

0 

Oct. 

158,803 

2,440 

0 

2,439 

284 

0 

Nov. 

156,080 

4,290 

28,967 

2,520 

0 

0 

Dec. 
Total  or 

72,456 

169.521 

29,672 

4,543 

0 

average 
1915 

124,593 

4,428 

8,211 

2,520 

0 

0 

Jan. 

116,814 

8,412 

19,214 

2,276 

0 

0 

Feb. 

117,112 

9,344 

0 

2,520 

0 

0 

Mar. 

126,748 

9,042 

0 

2,439 

353 

0 

April 

132,214 

9,344 

0 

2,520 

494 

0 

May 

140,250 

8,967 

0 

2,439 

603 

0 

June 

139,647 

7,010 

0 

2,520 

704 

0 

July 

136,423 

3,980 

0 

2,520 

644 

0 

Aag. 

133,259 

3,270 

0 

2,439 

492 

0 

Sept. 

130,328 

2,770 

0 

2,520 

369 

0 

Oct. 

127,439 

3,010 

0 

2,439 

244 

0 

Nov. 

124,750 

3,580 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

73,157 

27,425 

29,672 

3,903 

0 

1916 

122,236 

8,759 

56,341 

2,520 

0 

0 

Jan. 

202,616 

8,741 

99,326 

2,358 

0 

0 

Feb. 

131,591 

9,344 

4,593 

2,520 

0 

0 

Mar. 

149,934 

9,042 

0 

2,439 

399 

0 

April 

157,954 

9,130 

0 

2,520 

545 

0 

May 

156,159 

5,830 

0 

2,439 

646 

0 

June 

153,074 

4,770 

0 

2,520 

752 

0 

July 

149,802 

3,570 

0 

2,520 

690 

0 

Aug. 

146,592 

2,810 

0 

2,439 

525 

0 

&pt. 

143,628 

6,473 

0 

2,520 

395 

0 

[Oct. 

141,250 

4,130 

0 

2,439 

264 

0 

Nov. 

138,547 

5,253 

21,173 

2,520 

0 

0 

Dec. 

Total  or 

77,852 

181,433 

29,754 

4,216 

0 

average 

29—52411 


458 


WATER  RESOURCES  OF   CALIFORNIA. 


TABLE  17a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

FOR  FLOOD  CONTROL  AND 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 
Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 


Height  of  dam,  383  feet.   Capacity  of  reservoir,  180.000  acre-feet 

Constant  draft  of  22  second-feet  maintained,  other  drafts  only 

Run-off  at 

as  required  by  reservoir  operating  diagram 

Year  and 
month 

Flood  control 

Azusa  in 
acre-feet 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Passed  by 

dam  for 

prior  rights 

in  acre-feet 

water  passing 
Azusa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 

Constant  draft 
from  over-year 

storage 

(22  second-feet) 

in  acre-feet 

Evaporation 

from  reservoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

acre-feet 

1917 

Jan. 

9,280 

63,201 

8,172 

13,501 

1,352 

0 

0 

Feb. 

13,200 

49,456 

7,551 

0 

1,222 

0 

0 

Mar. 

13,600 

53,883 

9,344 

0 

1,352 

0 

0 

April 

10,500 

56,787 

9,042 

0 

1,309 

208 

0 

May 

8,610 

56,728 

8,531 

0 

1,352 

276 

0 

June 

5,270 

55,179 

5,270 

0 

1,309 

327 

0 

July 

3,140 

53,543 

3,140 

0 

1,352 

379 

0 

Aug. 

2,200 

51,812 

2,200 

0 

1.352 

345 

0 

Sept. 

],5i9 

50,115 

1,510 

0 

1,309 

262 

0 

Oct. 

1,560 

48,544 

1,560 

0 

1,352 

198 

0 

Nov. 

1,840 

46,994 

1,840 

0 

1,309 

127 

0 

Dec. 

2,000 

45,558 

2,000 

0 

1,352 

0 

0 

Total  or 
average 

72,710 

60,160 

13,501 

15.922 

2.122 

0 

1918 

Jan. 

2,020 

44,206 

2,020 

0 

1,352 

0 

0 

Feb. 

9,330 

42,854 

3,847 

0 

1,222 

0 

0 

Mar. 

73,200 

47.115 

9,249 

3,595 

1.352 

0 

0 

April 

17,000 

106,119 

9,042 

0 

1,309 

315 

0 

May 

10,000 

112,453 

8.993 

0 

1,352 

436 

0 

June 

6,010 

111,672 

6.010 

0 

1,309 

514 

0 

July 

3,970 

109,849 

3.970 

0 

1,352 

601 

0 

Aug. 

2,840 

107,896 

2,840 

0 

1,352 

551 

0 

Sept. 

2,330 

105,993 

2,330 

0 

1.309 

420 

0 

Oct. 

2,930 

104,264 

2,930 

0 

1,352 

319 

0 

Nov. 

3,140 

102,593 

3,140 

0 

1,309 

212 

0 

Dec 

4,370 

101,072 

4,370 

27,459 

1,352 

0 

0 

Total  or 

X  Utdl  Ul 

average 

137,140 

58,741 

31,054 

15,922 

3,368 

0 

1919 

Jan. 

3.300 

72,261 

3,300 

0 

1,352 

0 

0 

Feb. 

4,110 

70,909 

4,110 

0 

1,222 

0 

0 

Mar. 

6,110 

09.087 

6,110 

0 

1,352 

0 

0 

April 

6,010 

68.335 

6,010 

0 

1,309 

230 

0 

May 

3,810 

66,796 

3,810 

0 

1,352 

305 

0 

June 

1,890 

65,139 

1,890 

0 

1,309 

361 

0 

July 

1,320 

63,469 

1,320 

0 

1,352 

420 

0 

Aug. 

935 

61,697 

935 

0 

1,352 

385 

0 

Sept. 

1,010 

59,960 

1,010 

0 

1,309 

293 

0 

Oct. 

2,040 

.58,358 

2,040 

0 

1,352 

222 

0 

Nov. 

2,130 

56,784 

2,130 

0 

1,309 

143 

0 

Dec. 

5,340 

55.332 

5,209 

0 

1.352 

0 

0 

Total  or 
average 

38,005 

37,874 

0 

15.922 

2,359 

0 

1920 

Jan. 

3,260 

54,111 

3,260 

0 

1.352 

0 

0 

Feb. 

12,700 

52,759 

5,854 

0 

1.265 

0 

0 

Mar. 

30,200 

58.340 

9,344 

0 

1,352 

0 

0 

April 
May 

25,100 

83,844 

9,042 

0 

1,309 

284 

0 

12,600 

98,309 

9,344 

0 

1,352 

401 

0 

June 

7,380 

99,812 

7,349 

0 

1,309 

476 

0 

July 

4,670 

98,058 

4,670 

0 

1,352 

555 

0 

Aug. 

3.200 

96,151 

3.200 

0 

1,352 

512 

0 

Sept. 

2,030 

94,287 

2,030 

0 

1,309 

391 

0 

Oct. 

2,000 

92.587 

2,000 

0 

1,352 

295 

0 

Nov. 

2,380 

90.940 

2,380 

0 

1,.309 

194 

0 

Dec. 
Total  or 
average 

2,210 

89.437 

2,210 

16.619 

1,352 

0 

0 

113,730 

60,683 

16.619 

15,965 

3,108 

0 

THE    CONTROL   OF   FLOODS   BY   RESERVOIRS. 


459 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  SIZES  OF  RESERVOIR  OPERATING 
CONSTANT  DRAFT  ONLY. 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  17,  page  184.) 

Maximum  flood  control  reserve  131,000  acre-feet, 
feet  passed  for  prior  rights. 


Height  of  dam,  425  feet.    Capacity  of  reservoir,  240,000  acre-feet 

Constant  draft  of  41  second-feet  maintained,  other  drafts  only 

as  required  by  reservoir  operating  diagram 

Flood  control 

Year  and 
month 

Stage  of 
reservoir  at 
beginning 
of  month  in 

acre-feet 

Passed  by 

dam  for 

prior  rights 

in  acre-feet 

water  passing 
Azusa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 

Constant  draft 
from  over-year 

storage 

(41  second-feet) 

in  acre-feet 

Evaporation 

from  reservoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

acre-feet 

1917 

123,201 

8,172 

12,270 

2,520 

0 

0 

Jan. 

109,519 

7,551 

0 

2,276 

0 

0 

Feb. 

112,892 

9,344 

0 

2,520 

0 

0 

Mar. 

114,628 

9,042 

0 

2,439 

325 

0 

.^pril 

113,322 

8,531 

0 

2,520 

432 

0 

May 

110,449 

5,270 

0 

2,439 

508 

0 

June 

107,502 

3,140 

0 

2,520 

589 

0 

July 

104,393 

2.200 

0 

2,520 

539 

0 

Aug. 

101,334 

1,510 

0 

2,439 

408 

0 

Sept. 

98,487 

1,560 

0 

2,520 

305 

0 

Oct. 

95,662 

1.840 

0 

2,439 

202 

0 

Nov. 

93,021 

2,000 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

60,160 

12,270 

29,672 

3,308 

0 

1918 

90,501 

2,020 

0 

2,520 

0 

0 

Jan. 

87,981 

3,847 

0 

2,276 

0 

0 

Feb. 

91,188 

9.249 

0 

2,520 

0 

0 

Mar. 

152,619 

9,042 

0 

2,439 

403 

0 

April 

157,735 

8,993 

0 

2,520 

543 

0 

May 

155,679 

6,010 

0 

2,439 

644 

0 

June 

152,596 

3,970 

0 

2,520 

752 

0 

July 

149,324 

2,840 

0 

2,520 

688 

0 

Aug. 

146,116 

2,330 

0 

2,439 

525 

0 

Sept. 

143,152 

2,930 

0 

2,520 

395 

0 

Oct. 

140,237 

3,140 

0 

2,439 

262 

0 

Nov. 

137,536 

4,370 

2,982 

2,520 

0 

0 

Dec. 
Total  or 
average 

58,741 

2,982 

29,672 

4,212 

0 

1919 

132,034 

3,300 

0 

2,520 

0 

0 

Jan. 

129,514 

4,110 

0 

2,276 

0 

0 

Feb. 

127,238 

6,110 

0 

2,520 

0 

0 

Mar. 

124,718 

6,010 

0 

2,439 

341 

0 

April 

121,938 

3,810 

0 

2,520 

454 

0 

May 

118,964 

1,890 

0 

2,439 

533 

0 

June 

115,992 

1,320 

0 

2,520 

621 

0 

July 

112,851 

935 

0 

2,520 

567 

0 

Aug. 

109,764 

1.010 

0 

2,439 

430 

0 

Sept 

106,895 

2,040 

0 

2,520 

323 

0 

Oct. 

104,052 

2,130 

0 

2,439 

212 

0 

Nov. 

101,401 

5,209 

0 

2,520 

0 

0 

Dec. 
Total  or 

37,874 

0 

29,672 

3,481 

0 

average 
1920 

99,012 

3,260 

0 

2,520 

0 

0 

.Jan. 

96,492 

5,854 

0 

2,358 

0 

0 

Feb. 

100,980 

9,344 

0 

2,520 

0 

0 

Mar. 

125,316 

9,042 

0 

2,4.39 

361 

0 

April 

138,574 

9,344 

0 

2,520 

,500 

0 

May 

138,810 

7.349 

0 

2,439 

.595 

0 

June 

135,807 

4,670 

0 

2,520 

690 

0 

July 

132,597 

3,200 

0 

2,520 

633 

0 

Aug. 

129,444 

2,030 

0 

2,439 

480 

0 

Sept. 

126,525 

2,000 

0 

2,520 

363 

0 

Oct. 

123,642 

2,380 

0 

2,439 

238 

0 

Nov. 

120,965 

2,210 

0 

2,520 

0 

0 

Dec. 
Total  or 

60,683 

0 

29,754 

3,860 

0 

average 

460 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  17a  (Continued).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

FOR  FLOOD  CONTROL  AND 

Monthly  Summary  of  Computa 

(For  corresponding  yearly  sum 
Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 


H 

eight  of  dam,  383  feet.    Capacity  of  reservoir,  180,000  acre-feet 

Constant  draft  q 

f  22  second-feet 

maintained,  other  drafts  only 

Run-off  at 

aa  required  by  reservoir  operating  diagram 

Year  and 

1 

Flood  control 

month 

Azusa  in 

Stage  of 

water  passing 

Constant  draft  | 

acre-feet 

reservoir  at 

Passed  by 

Azusa  during 

from  over-year 

Evaporation 

Waste  over 

beginning 

dam  for 

flood  season  at 

storage 

from  reservoir 

spillway 

of  month  in 

prior  rights 

rates  less  than 

(22  second-feet) 

surface 

in  acre-feet 

acre-feet 

in  acre-feet 

1.900  second- 
feet  in 
acre-feet 

in  acre-feet 

in  acre-feet 

1921 

Jan. 

5,160 

71,466 

4,405 

18,459 

1,352 

0 

0 

Feb. 

4,490 

52,410 

4,490 

0 

1,222 

0 

0 

Mar. 

15,400 

51,188 

7.288 

0 

1.352 

0 

0 

April 

6,070 

57,948 

6,070 

0 

1,309 

206 

0 

May 

15,700 

56,433 

6,835 

0 

1,352 

282 

0 

June 

8,980 

63,664 

7,920 

0 

1,309 

361 

0 

July 

3,830 

63,054 

3,830 

0 

1,352 

418 

0 

Aug. 

2,450 

01,284 

2,450 

0 

1.352 

383 

0 

Sept. 

1,840 

59,549 

1,840 

0 

1,309 

293 

0 

Oct. 

2,040 

57,947 

2,040 

0 

1,352 

220 

0 

Nov. 

1,800 

56,375 

1,800 

0 

1.309 

143 

0 

Dec. 

119,000 

54,923 

5,045 

41,740 

1,352 

0 

0 

Total  or 
average 

186.760 

54,013 

60,199 

15,922 

2,306 

0 

1922 

Jan. 

62,100 

125,786 

9,344 

107,332 

1,352 

0 

0 

Feb. 

88,900 

69,858 

8,440 

83,316 

1,222 

0 

0 

Mar. 

47,800 

65,780 

9,344 

2,882 

1,352 

0 

0 

April 

31,400 

100,002 

9,042 

0 

1,309 

317 

0 

May 

24.700 

120,734 

9,344 

0 

1,352 

474 

0 

June 

14.400 

134,264 

9,042 

0 

1,309 

591 

0 

July 

9.100 

137,722 

•  8,576 

0 

1.352 

700 

0 

Aug. 

5,080 

136,194 

5,080 

0 

1.352 

646 

0 

Sept. 

3.290 

134,196 

3,290 

0 

1.309 

496 

0 

Oct. 

3,110 

132,391 

3,110 

0 

1,352 

375 

0 

Nov. 

5,310 

130,664 

4,519 

25,655 

1,309 

242 

0 

Dec. 

21,500 

104,249 

8.456 

52.740 

1.352 

0 

0 

Total  or 
average 

316.690 

87,587 

271.925 

15,922 

3.841 

0 

1923 

Jan. 

7,130 

63,201 

6.968 

12.056 

1.352 

0 

0 

Feb. 

7,830 

49,955 

7,791 

0 

1.222 

0 

0 

Mar. 

7,320 

48,772 

7,320 

0 

1,352 

0 

0 

April 
May 

8,330 

47,420 

8,079 

0 

1,309 

182 

0 

5,480 

46.180 

5.480 

0 

1.352 

244 

0 

June 

3.700 

44,584 

3.700 

0 

1.309 

288 

0 

July 

2.420 

42,987 

2.420 

0 

1.352 

331 

0 

Aug. 

1,990 

41.304 

1.990 

0 

1.352 

299 

0 

Sept. 

1,750 

39.653 

1,750 

0 

1.309 

232 

0 

Oct. 

1.710 

38,112 

1,710 

0 

1.352 

171 

0 

Nov. 

1.960 

36,589 

1.960 

0 

1.309 

111 

0 

Dec. 

2,130 

35,169 

2,130 

0 

1.352 

0 

0 

Total  or 

average 

61.750 

51,298 

13,056 

15.922 

1,858 

0 

1924 

Jan. 

2,170 

33,817 

2.170 

0 

1.352 

0 

0 

Feb. 

1.790 

32.405 

1,790 

0 

1,265 

0 

0 

Mar. 

4.130 

31.200 

3.714 

0 

1.352 

0 

0 

April 
May 

6,190 

30.264 

6,190 

0 

1.309 

141 

0 

3,650 

28,814 

3.650 

0 

1,352 

186 

0 

June 

1,660 

27,276 

1.660 

0 

1.309 

214 

0 

July 

1.000 

25.753 

1.000 

0 

1.352 

248 

0 

Aug. 

756 

24,153 

756 

0 

1,352 

222 

0 

Sept. 

744 

22,579 

744 

0 

1,309 

167 

0 

Oct. 

873 

21,103 

873 

0 

1,352 

123 

0 

Nov. 

1.190 

19,628 

1.190 

0 

1.309 

79 

0 

Dec. 
Total  or 

1.780 

18,240 

1,780 

0 

1.352 

0 

0 

average 

25.933 

25.517 

0 

15.965 

1,380 

0 

THE   CONTROL   OF   FLOODS  BY   RESERVOIRS. 


461 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  SIZES  OF  RESERVOIR  OPERATING 
CONSTANT  DRAFT  ONLY, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  17,  page  184.) 

Maximum  flood  control  reserve  131,000  acre-feet, 
feet  passed  for  prior  rights. 


Height  of  dam 

,  425  feet.    Capacity  of  reservoir,  240.000  acre-feet 

Constant  draft  of  41  second-feet  maintained,  other  drafts  only 

as 

required  by  reservoir  operatng  diagra 

m 

Flood  control 

Year  and 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Passed  by 

dam  for 

prior  rights 

in  acre-feet 

water  passing 
Aziisa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 
acre-feet 

Constant  draft 
from  over-year 

storage 

(41  second-feet) 

in  acre-feet 

Evaporation 

from  r«eervoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

month 

1921 

118,445 

4,405 

4,431 

2,520 

0 

0 

Jan. 

112,249 

4,490 

0 

2,276 

0 

0 

Feb. 

109,973 

7,288 

0 

2,520 

0 

0 

Mar. 

115,565 

6,070 

0 

2,439 

325 

0 

April 

112,801 

6,835 

0 

2,520 

436 

0 

May 

118,710 

7,920 

0 

2,439 

533 

0 

June 

116,798 

3,830 

0 

2,520 

623 

0 

July 

113,655 

2,450 

0 

2,520 

569 

0 

Aug. 

110,566 

1,840 

0 

2,439 

432 

0 

Sept. 

107,695 

2,040 

0 

2,520 

325 

0 

Oct. 

104,850 

1,800 

0 

2,439 

214 

0 

Nov. 

102,197 

5,045 

31,012 

2,520 

0 

0 

Dec. 
Total  or 
average 

54,013 

35,443 

29,672 

3,457 

0 

1922 

182,620 

9,344 

105,595 

2,520 

0 

0 

Jan. 

127,261 

8,440 

79,666 

2,276 

0 

0 

Feb. 

125,779 

9,344 

2,562 

2,520 

0 

0 

Mar. 

159,153 

9,042 

0 

2,439 

424 

0 

April 

178,648 

9,344 

0 

2,520 

611 

0 

May 

190,873 

9,042 

0 

2,439 

752 

0 

June 

193,040 

8,576 

0 

2,520 

894 

0 

July 

190,150 

5,080 

0 

2,520 

815 

0 

Aug. 

186,815 

3,290 

0 

2,439 

623 

0 

Sept. 

183,753 

3,110 

0 

2,520 

470 

0 

Oct. 

180,763 

4,519 

14,559 

2,439 

307 

0 

Nov. 

164,249 

8,456 

51,572 

2,520 

0 

0 

Dec. 
Total  or 
average 

87,587 

253,954 

29,672 

4,896 

1923 

123,201 

6,968 

10,928 

2,520 

0 

0 

Jan. 

109,915 

7,791 

0 

2,276 

0 

0 

Feb. 

107,678 

7,320 

0 

2,520 

0 

0 

Mar. 

105,158 

8,079 

0 

2,439 

305 

0 

April 

102,665 

5,480 

0 

2,520 

403 

0 

May 

99,742 

3,700 

0 

2,439 

474 

0 

June 

96,829 

2,420 

0 

2,520 

549 

0 

July 

93,760 

1,990 

0 

2,520 

500 

0 

Aug. 

90,740 

1,750 

0 

2,439 

379 

0 

Sept. 

87,922 

1,710 

0 

2,520 

288 

0 

Oct. 

85,114 

1,960 

0 

2,439 

186 

0 

Nov. 

82,489 

2,130 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

51,298 

10,928 

29,672 

3,084 

0 

1924 

79,969 

2,170 

0 

2,520 

0 

0 

Jan. 

77,449 

1,790 

0 

2,358 

0 

0 

Feb. 

75,091 

3,714 

0 

2,520 

0 

0 

Mar. 

72,987 

6,190 

0 

2,439 

238 

0 

April 

70,310 

3,650 

0 

2,520 

315 

0 

May 

67,475 

1.660 

0 

2,439 

369 

0 

June 

64,667 

1.000 

0 

2,520 

426 

0 

July 

61,721 

756 

0 

2,520 

385 

0 

Aug. 

58,816 

744 

0 

2,439 

290 

0 

Sept. 

56.087 

873 

0 

2,520 

214 

0 

Oct. 

53.353 

1.190 

0 

2,439 

139 

0 

Nov. 

60.775 

1.780 

0 

2,520 

0 

0 

Dec. 
Total  or 
average 

25,517 

0 

29,754 

2,376 

0 

462 


WATER  RESOURCES  OF    CALIFORNIA. 


TABLE  17a  (Concluded).     SAN  GABRIEL 

COMPARISON  OF  WATER  YIELD  FOR 

FOR  FLOOD  CONTROL  AND 

Monthly  Summary  of  Compute 

(For  corresponding  yearly  sum 
Maximum  controlled  flow  at  Azusa  1,900  second-feet. 

Natural  flow  up  to  152  second- 


Height  of  dam,  383  feet.    Capacity  of  reservoir,  180,000  acre-feet 

Constant  draft  of  22  second-feet  maintained,  other  drafts  only 

Run-off  at 

as  required  by  reservoir  operating  diagram 

Year  and 
month 

Flood  control 

Azusa  in 
acre-feet 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Passed  by 

dam  for 

prior  rights 

in  acre-feet 

water  passing 
Azusa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 

Constant  draft 
from  over-year 

storage 

(22seoond-feet) 

in  acre-feet 

Evaporation 

from  reservoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

acre-feet 

1925 

Jan. 

1,710 

16,888 

1,710 

0 

1,352 

0 

0 

,      Feb. 

1,620 

15,536 

1,620 

0 

1,222 

0 

0 

Mar. 

2,510 

14,314 

2,423 

0 

1,352 

0 

0 

April 

7,200 

13,049 

5,765 

0 

1,309 

89 

0 

May 

3,050 

13,086 

3,050 

0 

1,352 

105 

0 

June 

1,840 

11,629 

1,840 

0 

1,309 

131 

0 

July 

824 

10,189 

824 

0 

1,352 

141 

0 

Aug. 

621 

8,696 

621 

0 

1,352 

117 

0 

Sept. 

492 

7,227 

492 

0 

1,309 

81 

0 

Oct. 

87.S 

5,837 

873 

0 

1,352 

52 

0 

Nov. 

1,010 

4,433 

1,010 

0 

1,309 

28 

0 

Dec. 

1,650 

3,096 

1,650 

0 

1,352 

0 

0 

Total  or 
average 

23,400 

21,878 

0 

15,922 

744 

0 

192S 

Jan. 

1,540 

1,744 

1,540 

0 

1,352 

0 

0 

Feb. 

7,940 

392 

5,485 

0 

1,222 

0 

0 

Mar. 

3,650 

1,625 

3,650 

0 

1,352 

0 

0 

April 

69,000 

273 

8,233 

0 

1,309 

159 

0 

May 

13,000 

59,572 

9,142 

0 

1,352 

293 

0 

June 

5,500 

61,785 

5,500 

0 

1,309 

349 

0 

July 

3,120 

60,127 

3,120 

0 

1,352 

408 

0 

Aug. 

2,070 

58,367 

2,070 

0 

1,352 

373 

0 

Sept. 

1,580 

56,642 

1.580 

0 

1.309 

284 

0 

Oct. 

55,049 

Nov. 

Dec. 

Total  or 

average 

107,400 

40,320 

0 

11,909 

1,866 

0 

Total  for 

period, 

Jan.  1, 

1897,  to 

Oct.  1, 

1926 

3,731,977 

1,513,303 

"1,672,152 

473.905 

76,867 

3,351 

Average 

for 

period. 

Jan. 1, 

1897,  to 

Oct.  1, 

1926 

125,445 

50,867               "56,207  1 

15,930 

2.584 

113 

•  These  Bgures  contain  7601  acre-feet  total  or  an  average  of  256  acre-feet  per  season  of  water  contributed  from  outside 
the  exact  period  of  analysis.  In  the  computations  from  which  this  table  is  prepared,  the  water  in  storage  is  less  by  this  amount 
than  on  January  1,  1897,  the  beginning  of  the  period.  Since  in  the  comput'.ilions  this  water  was  released  as  flood  control  water 
during  the  first  flood  season  of  the  period,  the  exact  yield  of  flood  control  water  for  the  period  is  less  than  here  shown  by  this 
amount. 


THE   CONTROL   OF   FLOODS  BY   RESERVOIRS. 


463 


RESERVOIR  ON  SAN  GABRIEL  RIVER. 

TWO  SIZES  OF  RESERVOIR  OPERATING 
CONSTANT  DRAFT  ONLY, 
tions  Carried  out  on  a  Daily  Basis. 

mary,  see  Table  17,  page  184.) 

Maximum  flood  control  reserve  131,000  acre-feet, 
feet  passed  for  prior  rights. 


Height  of  dam 

425  feet.    Capacity  of  reservoir,  240,000  acre-feet 

Constant  draft  of  41  second-feet  maintained,  other  drafts  only 

as 

required  by  reservoir  operating  diagra 

m 

Flood  control 

Year  and 

Stage  of 
reservoir  at 

beginning 
of  month  in 

acre-feet 

Passed  by 

dam  for 

prior  rights 

in  acre-feet 

water  passing 
Azusa  during 
flood  season  at 
rates  less  than 
1,900  second- 
feet  in 
acre-feet 

Constant  draft 
from  over-year 

storage 

(41  second-feet) 

in  acre-feet 

Evaporation 

from  reservoir 

surface 

in  acre-feet 

Waste  over 

spillway 
in  acre-feet 

month 

1925 

48,255 

1,710 

0 

2,520 

0 

0 

Jan. 

45,735 

1,620 

0 

2,276 

0 

0 

Feb. 

43,459 

2,423 

0 

2,520 

0 

0 

Mar. 

41,026 

5,765 

0 

2,439 

171 

0 

April 

39,851 

3,050 

0 

2,520 

222 

0 

May 

37,109 

1.840 

0 

2,439 

254 

0 

June 

34,416 

824 

0 

2,520 

288 

0 

July 

31,608 

621 

0 

2,520 

256 

0 

Aug. 

28,832 

492 

0 

2,439 

188 

0 

Sept. 

26,205 

873 

0 

2,520 

137 

0 

Oct. 

23,548 

1,010 

0 

2,439 

85 

0 

Nov. 

21,024 

1,650 

0 

2,520 

0 

0 

Dec. 
Total  or 

21,878 

0 

29,672 

1,601 

0 

average 
1923 

18,504 

1,540 

0 

2,520 

0 

0 

Jan. 

15,984 

5,485 

0 

2,276 

0 

0 

Feb. 

16,163 

3,650 

0 

2,520 

0 

0 

Mar. 

13,643 

8,233 

0 

2,439 

196 

0 

April 

71,775 

9,142 

0 

2,520 

325 

0 

May 

72,788 

5,500 

0 

2,439 

385 

0 

June 

69,964 

3,120 

0 

2,520 

442 

0 

July 

67,002 

2,070 

0 

2,520 

403 

0 

Aug. 

64,079 

1,580 

0 

2,439 

303 

0 

Sept. 

61,337 

Oct. 

Nov. 

Dec. 

Total  or 

40,320 

0 

22,193 

2,054 

0 

average 

Total  for 
period, 
Jan.l, 
1897,  to 
Oct.  1, 

1,513,303 

1-1,297,000 

i>883,173 

99,814 

0 

1926 

Average 
for 

period, 
June  1, 
1897,  to 
Oct.  1, 

50,867 

1^43,597 

''29,686 

3,355 

0 

1926 

•>  These  figures  contain  61 ,313  acre-feet  total  or  an  average  of  2060  acre-feet  per  season  of  water  contributed  from  outside 
the  exact  period  of  analysis.  In  the  computations  from  which  this  table  is  prepared  the  water  in  storage  on  October  1.  1926, 
the  end  of  the  period,  is  less  by  this  aomunt  than  on  January  1,  18!J7,  the  beginning  of  the  period.  A  supplementary  analysis, 
having  the  same  amount  of  water  in  storage  at  the  beginning  and  at  the  end  of  the  period  was  made  to  obtain  the  exact  yield 
for  the  period.  This  gave  47,900  and  23,300  acre-feet  per  season  respectively  for  the  flood  control  water  and  uniformly  con- 
continuous  flow  instead  of  43,597  and  29,686  acre-feet  respectively  that  are  shown  herein. 


52411      10-28      5M 


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UiaVKRSITY  OF  CALIFORNtA 

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